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Bridging 

9

T0008-16F

Release 5.2M

Bridging Features and Capabilities

MAC Addressing

What Is It?

Bridges, whether they using Transparent Bridging, operate at the Data Link Layer, 
which is concerned with MAC addressing. The MAC Address is a 6-byte MAC 
(Media Access Control) address that identifies stations on a LAN. The IEEE 
administers distribution of the MAC address to ensure no duplicates occur in MAC 
addressing. This is accomplished by assigning a unique MAC address to each 
manufacturer. Each manufacturer then assigns sequential values to the lower three 
bytes for each interface manufactured.

For More Details

For more details on MAC Address filtering, see the section “MAC Address 
Filtering” section on page 58”in this manual.

Summary of Contents for PathBuilder S200 Series

Page 1: ...3Com Corporation PathBuilder S200 Series Switch Bridging ...

Page 2: ...f the software is procured for use by the Department of Defense the following legend applies Restricted Rights Legend Use duplication or disclosure by the Government is subject to restrictions as set forth in subparagraph c 1 ii of the Rights in Technical Data and Computer Software clause at DFARS 252 227 7013 If the software is procured for use by any U S Government entity other than the Departme...

Page 3: ...closed to others published or used in whole or in part for any purpose other than that for which it is being made available Use of software described in this document is subject to the terms and conditions of the 3Com Software License Agreement This document is for information purposes only and is subject to change without notice Part No T0008 16 Rev F First Printing October 1998 Manual is current...

Page 4: ......

Page 5: ...g Solutions PathBuilder S200 series switches are intended for use in remote bridging solutions This means the PathBuilder S200 series switch is best used to connect a remote LAN to the WAN to connect to other remote LANs in your network as shown in Figure 1 Figure 1 PathBuilder S200 Series Switch Bridge Combining Traffic from Serial Devices Figure 1 shows PathBuilder S200 series switches acting as...

Page 6: ...ge 37 No Local Bridging As mentioned earlier PathBuilder S200 series switches are not intended for use in local bridging applications where one LAN is connected directly to another LAN It is not recommended you use PathBuilder S200 series switches to perform local bridging Transparent Bridging Transparent Bridging TB is the method used by PathBuilder S200 series switches to bridge Ethernet LAN tra...

Page 7: ...g Source Route Bridging Operation 45 Connecting a Station to a Server in Source Route Bridging 47 Transparent Bridging for Ethernet LANs 53 Forwarder Database and Spanning Tree 58 Using Filters 59 Transparent Bridge Configuration Parameters 61 Bridge Filtering 62 MAC Address Filtering 63 MAC Address Filtering Examples 67 Identifying Address Links for MAC Addressing 72 MAC Wildcard Filtering 73 Con...

Page 8: ... Detailed Bridge Link Statistics 135 Bridge Link Filter Summary 138 Transparent Bridge Forwarding Table Statistics 140 Transparent Bridge Detailed Bridge Link Statistics 142 LAN Connection Statistics 144 LLC2 LT Session Summary Statistics 149 LLC2 LT Detailed Session Statistics 151 Reset Statistics 155 ...

Page 9: ...p to two 802 3 Ethernet LAN interfaces per node or one 802 5 Token Ring LAN interface per node and up to 32 remote bridge connections A PathBuilder S200 series switch bridge can be connected to a WAN backbone made up of X 25 Frame Relay or both as shown in Figure 2 Figure 2 Example of Typical PathBuilder S200 Series Switch Bridging Application PathBuilder S200 series switches are best suited for r...

Page 10: ...ocols over the Wide Area Network WAN to remote destinations Supported protocols include Novell Netware DECnet Banyan Vines Example of Basic Ethernet Frame Format Figure 3 shows the basic frame formats for Ethernet frames supported by PathBuilder S200 series switches Figure 3 Frame Format for Ethernet Frames 802 3 MAC Frame Format Figure 4 shows the supported 802 3 Ethernet MAC Frame format Figure ...

Page 11: ...Ns connected across a WAN using two PathBuilder S200 series switches as bridges The example shows a Frame Relay WAN application but you can also bridge across an X 25 WAN Figure 5 Ethernet Bridge Example For More Details For more details on bridging Ethernet LAN traffic see Transparent Bridging for Ethernet LANs on page 48 Frame Relay PB S200 PB S200 ...

Page 12: ...gure two Ethernet LAN interfaces in the same node instead of a mix of one Ethernet and one Token Ring you can perform local Transparent bridging between the two Ethernet LANs Figure 6 Example of Mixed LAN Bridging in PathBuilder S24x 26x and 27x Switch Note Mixed LAN operation does not support translational bridging meaning you cannot pass LAN traffic from an Ethernet LAN to a Token Ring LAN witho...

Page 13: ...ntrol address that identifies stations on a LAN The IEEE administers distribution of the MAC address to ensure no duplicates occur in MAC addressing This is accomplished by assigning a unique MAC address to each manufacturer Each manufacturer then assigns sequential values to the lower three bytes for each interface manufactured For More Details For more details on MAC Address filtering see the se...

Page 14: ...icient means for carrying out an LLC2 session between two SNA end stations attached to separate Token Ring LANs connected by a Wide Area Network WAN Additionally Local Termination provides detailed statistics on LLC2 sessions LT Example Figure 7 shows a network where running LLC2 Local Termination at the edge point PathBuilder S200 series switches enables spoofing from one side of the network to t...

Page 15: ...Termination LT Station tables It does not interfere with previously configured Local Termination spoofing sessions Example Figure 8 shows how a PathBuilder S200 series switch automatically learns the address of PCs connected to the local bridge so you can pass data traffic to the host without configuring entries in the Local Termination Station table for each PC session Figure 8 Example of Local T...

Page 16: ...e Filtering feature of PathBuilder S200 series switches lets you restrict or filter all NetBIOS broadcasts except those to or from a list of servers NetBIOS Name Filtering compares NetBIOS broadcasts to a pattern that may have a wild card character at the end For example if all servers have a naming convention with the first part of the name the same for example SVR then you can complete only one ...

Page 17: ...lder S200 series switch implementation of the Spanning Tree Protocol Entity SPTE conforms to IEEE 802 ID specifications Refer to the IEEE 802 ID specification for more detailed information on Spanning Tree Protocol operation Automatic Manual Spanning Tree Support PathBuilder S200 series switch support both automatic and manual spanning tree operations If you do not want to configure spanning tree ...

Page 18: ... can connect up to two Ethernet LANs to a single PathBuilder S24x 26x and 27x switch to perform bridging and routing of LAN traffic across the WAN to multiple Ethernet LANs Before Dual Ethernet LAN the PathBuilder S24x 26x and 27x switch supported only one Ethernet LAN port for remote bridging and routing of LAN traffic For More Details See the Dual LAN Ethernet section on page 117 ...

Page 19: ...al Circuit PVC for Frame Relay Figure 9 PB S200s Connecting LANs via an X 25 Frame Relay Link Extended Bridging for Multiple LANs If more than two remote LANs are involved in your bridging application the bridge arrangement can be extended so that individual LAN pairs are connected by different bridges as shown in Figure 10 Figure 10 Two Port Bridges Connecting Multiple Token Ring LANs In this exa...

Page 20: ...ge away from Token Ring 2 and Token Ring 3 and the same applies for the other rings From a bridged network point of view Token Ring 1 is one bridge away from Token Ring 3 but Node 1 is not directly connected to Node 3 Traffic between Token Ring 1 and Token Ring 3 does not have to pass through Token Ring 2 This is an important advantage in configuring bridge networks with the PathBuilder S200 serie...

Page 21: ...provides the network services that the bridge requires in order to function over the WAN network The principal service is establishing and maintaining SVC PVC for Frame Relay connections to remote LAN bridge forwarders so that virtual circuits can be formed between the forwarders The bridge sees the LAN and the WAN by means of the WAN Adapter as networks it is attached to by links There are a tota...

Page 22: ...18 Bridging Bridge Hardware Components in PathBuilder S200 Series Switches ...

Page 23: ... such as X 25 Frame Relay or other proprietary protocols Codex Proprietary Protocol ID The Protocol Identifier ID is placed on the Call User Data field of the Call Request packet This packet is generated by the Autocall used to establish a circuit for a bridge link If the bridge link is not configured to initiate an autocall then this configured value is matched with that found in an Incoming Call...

Page 24: ... and the LAN Connection Subaddress specified in the LAN Connection Table are verified and allowed to connect to the WAN Adapter in order to reach the LAN bridges The LAN Connection Subaddress is appended to the calling address of the Call Request packet if generated and sent by the WAN Adapter Use the default value unless it conflicts with an address already in use Refer to the LAN Connection Tabl...

Page 25: ...ord Bridge Link Record LAN Connection Table Optional Filter Tables LAN Server Subsystem LSS Record optional Autocall Mnemonic Table Some of the WAN Adapter connections are configured to Autocall Routing Table At the destination node a LAN Connection LCON entry is needed for the WAN Adapter For general details on configuring the Node record and the LAN Port record refer to the PathBuilder S200 Seri...

Page 26: ...4 Configure Bridge Parameters Parameters These parameters make up the Bridge Parameter Record Node Address Date Time Menu Configure Bridge Path Bridge Parameters Max Number of Bridge Links STPE Control Bad Hello Threshold Bad Hello Timeout Learn Only Period Aging Period Bridge WAN Data Priority Bridged Protocols Local Bridge ID Maximum Number of Bridge Links Range 36 to 250 Default 36 Description ...

Page 27: ...ned to the different links Bridge protocol data units BPDUs are special frames used to continually communicate this information between bridges MAN The Spanning Tree is configured by the network administrator This is done using the STPE Link State parameter found in the next section Bridge Link Parameters Configure all bridges in your network to MANual if you are not an expert user of Spanning Tre...

Page 28: ...a bridge is prevented from forwarding frames after the forwarding is cleared due to a node boot Bad Hello Timeout continued Aging Period used for Ethernet only Range 2 to 1000000 Default 10 Description Specify the time in seconds that a learned entry in the Forwarding Table is allowed to remain in the table without being updated relearned If the entry is not updated within this time period it is d...

Page 29: ...dged Protocols Range None IP IPX Default None Description Specify the routable protocols that can be bridged across BROUT or BRID links None specifies no routable protocols IP IPX will be bridged IP specifies that IP packets can be bridged IPX specifies that IPX packets can be bridged Note Any combination of the available selections may be specified by summing such as IP IPX ...

Page 30: ...t you establish and maintain SVC connections to a remote LAN bridge The bridge views the LAN bridge links and the WAN bridge links as links to the networks attached to it Bridge Link Parameters Figure 15 shows the Bridge Link parameters Figure 15 Configure Bridge Link Menu Node Address Date Time Menu Configure Bridge Path Bridge Parameters Bridge Link Parameters Entry Number Bridge Type Bridge ID ...

Page 31: ...ted to a remote bridge link and such an arrange ment forms a bridge between the two LANs At the destination node the routing table must have an entry that lists the destination port as LCON LAN Connection This allows the call to be directed to a connection on the WAN Adapter Bridge_Type Range SR TB BOTH_SR_AND_TB Default TB Description This is the bridge type for links connecting to WANs It define...

Page 32: ...r a modification of the Routing Control field of RIF is necessary MAC Address Filter Action Range NONE PASS BLOCK Default NONE Description Specify how the MAC Address Filter Table is used NONE No MAC address filtering using the MAC Address Filter Table is performed for this link PASS Look in the MAC Address Filter Table for an entry with a matching MAC frame address and take the filtering action s...

Page 33: ...ound this value indicates that this frame should be passed BLOCK Look in the Protocol Filter Table for an entry with a matching frame address and take the filtering action specified by this filter table If no matching entry is found this value indicates that this frame should be blocked NETBIOS Name Filter Action Range PASS BLOCK NONE Default NONE Description Specify how NetBIOS Name Filter is use...

Page 34: ...tions RFC1294 Bridge link uses RFC1294 or RFC1490 bridging to connect to another Bridge or Frame Relay Access Device A Bridge Link Virtual Ring Number is required TRANS Translational Bridging support for PathBuilder S24x 26x and 27x switch only Boot Type A change to this parameter requires a node boot to take effect Virtual Ring Number Range 0001 0FFF hexadecimal Default 0000 Description This is a...

Page 35: ... LAN Connection Table parameters Figure 16 LAN Connection Table Menu Parameters These parameters make up the LAN Connection Table Record Node Address Date Time Menu Configure Path Node Port LAN Connection Table Entry Number LAN Forwarder Type LAN Connection Type Router Interface Number Encapsulation Type Autocall Mnemonic LCON Queue Limit Billing Records Traffic Priority Entry Number Range 1 to 32...

Page 36: ...Connections If configured as GROUP multiple LAN Connections can use the same Router Interface number If configured as PT_to_PT the Router Interface configured must be unique to this LAN Connection Note This parameter appears if the LAN Forwarder Type is configured as ROUT or BROUT Boot Type When changing from GROUP to PT_PT a Node boot is required Otherwise a Table and Node Record boot is required...

Page 37: ...nnection is configured to autocalling A corresponding entry must be made in the Mnemonic Table A blank entry means autocalling will not be initiated by this LAN connection entry The LAN connector at the remote device must initiate the call If configured the Autocall Mnemonic references a remote address which will be called by the LAN connection Specifically it must equal the node address of the no...

Page 38: ...H Description Specify the Traffic Priority level of this LAN Connection LOW One Low Priority packet is sent for every Traffic Priority Step number of Medium priority packets MED One Medium priority packet is sent for every Traffic Priority Step number of High priority packets HIGH High is the first level of priority packets sent if no expedite priority packets are sent EXP Expedite priority packet...

Page 39: ...ue where the link speed is approximately 10 Mbps On a WAN link it becomes an issue because the transmission times for large frames become significant Example of Frame Sizes Figure 17 shows the effect on transit delay across a network for two cases in one an end system sends a large packet as a single frame and in the other the same large packet is sent as three smaller packets Figure 17 How Packet...

Page 40: ... for transmitting a frame becomes long enough that the probability of an error occurring during the transmission time is likely An error on a large frame with its subsequent retransmission means the media are used with unproductive transmissions and reduced efficiency Standard Frame Sizes In general these industry standards can be used as a guideline for selecting the maximum frame size Bridge Tra...

Page 41: ... Link Parameters Record Also be sure the parameter Virtual Ring Number is set to a unique value Configuration Guidelines These factors should be considered when configuring your PathBuilder S24x 26x and 27x switch for Translational Bridging Only one link in a PathBuilder S24x 26x and 27x switch can have the param eter Link Mode TRANS Only Bridge Link with Bridge Type SR can have Link Mode TRANS LL...

Page 42: ...N 2 Bridge Link 6 Source Bridge Bridge Link 2 Token Ring Bridge Link 5 Bridge Type TB LAN Connection 1 LAN Forwarder Type BRID Bridge Link Number 5 Bridge Link 6 Bridge Type SR Link Mode TRANS Virtual Ring Number 2 LAN Connection 2 LAN Forwarder Type BRID Bridge Link Number 6 Network Services PVC Setup Table Source LCON 1 Destination LCON 2 SVC PB S200 Node 100 Station A Station B Port 13 Port 13 ...

Page 43: ...ute broadcast is disabled the frame is not copied If the frame is All Route Broadcast then the Routing Information field must not contain the remote ring number These rules apply to frames with either locally or universally administered addresses and for frames with either individual or group addresses Broadcast Frame Handling When the All Route Broadcast frame is received from the LAN and initiat...

Page 44: ...col ID must be specified in the Node Record to ensure that calls for other traffic types if mistakenly connected to the bridge subaddress are rejected Only similar remote bridges must identify themselves with this ID For details on configuring the Node record refer to the PathBuilder S200 Series Basic Protocols Individual Bridge Links Once you complete node and port configuration individual bridge...

Page 45: ... WAN Side The WAN Adapter default subaddress 94 is used to make the transition from the LAN to the WAN The WAN links are numbered 5 to 36 and provide up to 32 WAN connection links which correspond to potential bridges These links pass the LAN traffic from the LAN Bridge to the WAN Adapter Refer to the sections on Bridge software modules and links for more information WAN Adapter The WAN Adapter ad...

Page 46: ... 21 Figure 21 Example of a Station to Server Configuration 2 The PC assumes the server is on the local LAN and the PC sends an LLC frame typically an LLC1 TEST frame around its local LAN AAA looking for a response from the server The TEST frame has a destination MAC Address equal to the server s MAC Address Since the server is not on the local ring no station responds to the server s destination M...

Page 47: ... frame includes the following Destination Address is server s MAC Address Routing Information Indicator bit RII is set to one This bit is the most significant bit in the source address indicating this frame has a Routing Information Field RIF Three bits in the Routing Information Field RIF indicate this is an ARE This instructs all bridges that encounter this frame to forward the frame to their de...

Page 48: ...d SVC which connects it across the WAN to a remote node Figure 25 Note that in the node attached to LAN AAA three bridge links 5 6 and 7 to the WAN side are necessary because they go to the three remote LANs to establish complete bridges to those LANs The three right hand nodes really need only one WAN Bridge Link each but two additional ones are shown they could be attached to other bridges in ot...

Page 49: ...ne of the ARE frames finds the destination server and the server recognizes the MAC address in the TEST frame LAN Port WAN Adaptor 5 6 7 1 LAN AAA LAN Port WAN Adaptor 5 6 7 1 LAN xxx LAN Port WAN Adaptor 5 6 7 1 PB S200 LAN zzz LAN Port WAN Adaptor 5 6 7 1 Bridge Bridge Bridge Bridge WAN Network LAN CCC PC Server WAN Bridge Link LAN Bridge Link PB S200 PB S200 PB S200 ...

Page 50: ... The response TEST frame also has a Routing Information Field RIF with the same path trace as the original ARE TEST frame except the Direction bit is set to 1 This reverses the direction in which the RIF sequence is read and indicates the path back to the source The RIF also sets three bits in the Routing Type field that indicate the frame is to be specifically routed and not broadcast 10 When the...

Page 51: ...so sends the RPS its adapter software level as well as its Upstream Neighbor Address If Then An RPS is present on the ring It responds to the station s request by sending it the current values for the ring s operational parameters The RPS then notifies the LAN managers that a new station has attached to the ring An RPS is not present on the ring The ring station uses the values assigned by the pro...

Page 52: ...dging forwarder table along with the link that the PathBuilder S200 series switch received the frame on if the address is not to be filtered When a transparent bridge receives a frame it checks its database for the frame address and performs one of the following actions If the frame s MAC destination address is not found in the TB forwarding table then the bridge sends the frame on all bridge conn...

Page 53: ... in the forwarding table Is the MAC Destination Address in the forwarding table TB Forwarder checks if any filters are set Do filters match TB Forwarder gives the frame to the appropriate handler as found in the forwarding table Drop the frame Do filters match TB Forwarder checks if any filters are set Do filters match Drop the frame Handler sends the frame Is the inbound flag for a Unicast or Mul...

Page 54: ... the aging process for LAN traffic The Hardware Accelerator applies the aging process to the learned addresses on a LAN port It needs to Set the aging timer bit for each address learned on the LAN link Reset the aging timer bit for the entry whenever a frame with the same source address passes through the bridge Decrement the aging timer bit when it receives periodic timeout notification from the ...

Page 55: ...e link where the frame arrived Before sending the frame out to each link the Forwarder checks with the filtering facility to see if filters are to be applied to the frame at that link If not the Forwarder sends the frame over to the link A multicast Broadcast frame is a frame with the Least Significant Bit of its destination address being set to 1 Whether the received non multicast and non broadca...

Page 56: ... the forward state once it is determined that the link should be part of the spanning tree This timer is set to avoid bridge topology loops from forming The Learn Only Period timer prevents the bridge from sending broadcasts as part of the learning process when the bridge first comes up and has a sparse forwarding database Aging Aging is an important process associated with the learned database en...

Page 57: ...ng database is as noted previously The permanent database offers a means of quickly obtaining a forwarding database without the bridge having to broadcast frames for which it does not know the destination link However since the bridge topology can change in an unpredictable way corresponding to unpredictable network failures it is best that the entries in the database are all aged Aging all entrie...

Page 58: ...r The Outgoing Source Address Filter filters packets based on their source address and the outgoing links Frames with a source address found in the Outgoing Source Address Filter List are discarded This filter may be applied to all links or selected links Outgoing Destination Address Filter The Outgoing Destination Address Filter filters packets based on their destination address and the outgoing ...

Page 59: ...ame is sent out over a link with the Multicast Protect Flag set and if its destination address is not found in the Permanent Station Address List the frame is dropped Once the Multicast Protect Flag is set for a link source address learning for multicast broadcast frames is stopped for that link totally and all the addresses that were learned before are moved into the Permanent Station Address Lis...

Page 60: ...k Parameters MAC Address Filter Table Protocol Filter Table NETBIOS Name LSS Parameters TB Forwarding Table Entry Number Local MAC Address Bridge Link Number Entry Number Range 1 to 8000 Default 1 Description Entry used to reference this table record Local MAC Address Range 00 00 00 00 00 01 to FF FF FF FF FF FF Default 00 00 00 00 00 01 Description MAC Address that is to be used for forwarding Br...

Page 61: ...ltering is Used Filtering is used to Reduce unnecessary traffic affecting the performance of LAN segments Filtering broadcasts can help to reduce this overhead Control the unnecessary proliferation of application level broadcasting used on Novell and NetBIOS applications Restrict access to certain LAN segments for security reasons Prevent unnecessary traffic from proliferating onto the WAN where b...

Page 62: ...ction STPE Link State STPE Priority STPE Path Cost MAC Address Filter Table Parameters The MAC Address Filter Table specifies The MAC Address of the frame to be filtered The filtering action to perform on the frame This table is used in conjunction with the Bridge Link Table to specify filtering action and includes the link action parameters which allow you to apply filtering action to every link ...

Page 63: ...a match occurs between the MAC address in the frame and an address contained in an entry in the MAC Address Filter Table Outgoing Destination Address Link Action Perform filtering action on an outbound frame for the indicated MAC Destination address List of Links Specifies the links associated with the preceding link action parameters in this table When Passlist PL is specified the associated list...

Page 64: ...Record or Entry MAC Address Filtering Action Setting Check MAC Address Filter Table for match of frame MAC Address Frame MAC Address in MAC Address Filter Table Check Bridge Link Table Pass frame without filtering NONE PASS BLOCK Block the frame Pass the frame Apply Table Filter PASS or BLOCK YES NO MAC Address Filtering Action Setting PASS or BLOCK ...

Page 65: ...ameters refer to Configuring the MAC Address Filter Table section on page 66 Incoming and Outgoing Frames The filtering action is applied to each link The frames passing on a link can be either incoming or outgoing see Figure 31 Incoming means that the frame is entering the bridge from elsewhere either from the LAN or WAN Outgoing means the frame is leaving the bridge Therefore a given frame can b...

Page 66: ... link 1 Incoming Source Address frames with MAC Address A are passed and Outgoing Source Address frames with MAC Address A are passed on link 5 but blocked on link 6 Figure 32 Example of Bridge Links Configured to Filter Selected MAC Address Frames How To Configure the Example in Figure 32 To configure something similar to Figure 32 complete the Bridge Link record for the bridge and the MAC Addres...

Page 67: ...lter Table filtering is performed on the frame as specified in this table The MAC Address Filter Table used in this example specifies the filtering to be performed on MAC Address A as the incoming source address to the bridge Frames with Incoming Source Address A are passed at link 1 see Figure 32 Frames with Outgoing Source Address A are passed at link 5 to server B but not passed on link 6 to se...

Page 68: ...path for a frame to go from the bridge to the LAN Example of Address Links Figure 33 shows that link 5 serves as both the Outgoing Source Address link and the Incoming Destination Address link In this example Outgoing Source Address link 5 allows the File Server with MAC Address 10 00 5A 00 00 40 the source to send frames to the WAN via link 5 Incoming Destination Address link 5 allows the File Se...

Page 69: ...ring lets you configure a smaller MAC Address Filter table if you configure MAC Address filters where one or more of the 12 character positions can be allowed to take any value in the permissible range For example with the existing functionality if the Bridge had to be configured to block all the frames with MAC addresses in the range 080004001F00 to 080004001FFF you would have to configure 256 fi...

Page 70: ...bridge link are to be filtered according to the entries in the MAC Address Filter Table The filter table is examined to see if there is a match If a match is found table and frame additional table parameters determine when to pass or block the frame If there is no match the decision is dependent upon the Bridge Link record to determine whether to pass or block Action is then taken on what is speci...

Page 71: ... Default PASS Description Incoming source means that the frame is entering the bridge entity from the LAN that includes the MAC address the source Therefore a given source frame will be incoming from the LAN to the Bridge and outgoing from the Bridge to the WAN provided it does not get blocked due to filtering Refer to Figure 31 PASS Pass incoming frames with this MAC Address value on all links th...

Page 72: ...ck list is specified by the parameter List of Links Links in this list block the frame Links not in this list pass the frame Incoming Destination Address Link Action Range PASS BLOCK PASSLIST BLOCKLIST Default PASS Description A Destination Address link allows a device on a Token Ring to receive frames An Incoming Destination Address link provides a path for a frame to go from the WAN to the bridg...

Page 73: ... prompt would wrap to MAC Address to allow further configuration of this record If this value is chosen skip List of Links parameter PASSLIST If this value is used a pass filtering list is specified by the parameter List of Links Links in this list pass the frame Links not in this list block the frame BLOCKLIST If this value is used a block filtering list is specified by the parameter List of Link...

Page 74: ...the Bridge Link Table of the bridge link involved with the frame to see if the Protocol Filtering Action parameter is configured to disable all filtering on that bridge link Figure 30 which describes the MAC Address filtering process is also applicable to protocol filtering For example if the parameter is configured to disable filtering NONE selected then the frame is allowed to pass and no filter...

Page 75: ...nges to the Protocol Filter Table parameters Protocol Filter Table Parameters Figure 36 shows the Protocol Filter Table parameters Figure 36 Configure Protocol Filter Table Menu Parameters These parameters make up the Protocol Filter Table Record Node Address Date Time Menu Configure Bridge Path Bridge Parameters Bridge Link Parameters MAC Address Filter Table Protocol Filter Table Entry Number Pr...

Page 76: ...eader which identifies the 3 byte Organizationally Unique Identifier OUI and 2 byte Protocol Type used for the frame This type includes Protocol OUI IP hex value AppleTalk Phase II 08 00 07 80 9B Apple ARP Phase II 00 00 00 80 F3 Proteon Proprietary AppleTalk Phase I for FDDI 00 00 93 80 02 Proteon Proprietary AppleTalk ART Phase I for FDDI 00 00 93 80 02 Note The protocols listed here represent o...

Page 77: ...in this list block the frame Links not in this list pass the frame An empty list means all links will pass Outgoing Protocol Link Action Range PASS BLOCK PASSLIST BLOCKLIST Default PASS Description Specifies the action to be taken on the outgoing protocol These actions include PASS BLOCK PASSLIST or BLOCKLIST PASS If this value is used outgoing frames with the specified protocol value are passed o...

Page 78: ... SNAP Protocol ID The SNAP is five bytes and is also found in the LLC field The first three bytes are OUI and the last two bytes are the Protocol ID Figure 38 Figure 38 SNAP Protocol ID The SNAP format is used to identify Ethernet and pre IEEE 802 protocol IDs that do not fit the 1 byte ID DSAP SSAP Control LLC Info LLC Field DSAP SSAP Control 5 Bytes LLC Field AA AA Type 2 Bytes OUI 00 00 00 03 A...

Page 79: ...0 0xFF DSAP 0000000000 FF FF SNAP Incoming Protocol Link Action Specifies the action to take on the incoming protocol Actions include Pass Block Passlist and Blocklist Outgoing Protocol Link Action Specifies the action to take on the outgoing protocol Actions include Pass Block Passlist and Blocklist List of Links Specifies the links associated with the preceding link action parameters in this tab...

Page 80: ...t Output System NetBIOS is a session level protocol standardized by IBM that serves as one of the main Application Programming Interfaces APIs for local area network software Software such as SNA 3270 emulation packages and Lotus Notes operate on top of the NetBIOS layer Microsoft LAN Manager uses NetBIOS extensively for identifying clients and servers NetBIOS is based on 16 character named servic...

Page 81: ...ers such as that matches any character or at the end of the pattern that matches all remaining characters As a result a single filter record can pass or block a large set of NetBIOS names Unlike current MAC Filter and Protocol filters for a bridge a packet may match more than one filter record For this reason NetBIOS Name Caching operates using an ordered list of name matching records A packet is ...

Page 82: ...er NetBIOS Name Filter Action in the Bridge Link Parameters record Figure 40 Bridge Link Parameters Record Step Action 1 Configure the NetBIOS Name Filter Action parameter in the Bridge Link Parameters 2 Configure the parameters in the NetBIOS Name Filter Table record Entry Number Hop Count Limit Largest Frame Size MAC Address Filter Action Protocol Filter Action NetBIOS Name Filter Action STPE Li...

Page 83: ...links start at entry 5 2 Enter the number of the link that you are defining and complete the NetBIOS Name Filter Action parameter using the description in the Parameters section that follows NetBIOS Name Filter Action Range PASS BLOCK NONE Default NONE Description When using NetBIOS Name Filters set the NetBIOS Name Filter Action to BLOCK on Bridge Link 1 the LAN link Then define the NetBIOS Name ...

Page 84: ... MAC Address Filter Table Protocol Filter Table NetBIOS Name Filter Table LSS Parameters LLC LT Station Table LLC LT WAN Parameters LLC LT Profile Table Enter Selection Step Action Result 1 Select Configure Configure Bridge NetBIOS Name Filter Table from the CTP Main menu The first entry of the NetBIOS Name Filter Table appears Note You can enter up to 255 entries in the table Each entry can be a ...

Page 85: ...ans that you enter ASCII characters for the name The name is left justified blank filled to the 15th byte and the 16th byte is ignored Hex means that you enter hexadecimal values for up to all 16 bytes The string is left justified and the remaining bytes are ignored NetBIOS Name Range 0 to 16 ASCII characters if parameter String Type ASCII Blank set to null 2 to 32 hexadecimal digits if parameter ...

Page 86: ...ist of Links parameter Links that are listed block the frame Links that are not listed pass the frame An empty list means that all links pass frames Note If you chose PASS or BLOCK skip the List of Links parameter Incoming NetBIOS Name List of Links Range 1 5 to 36 Default The individual numbers correspond to the links that you filter according to the preceding parameter Description The following ...

Page 87: ...lock the frames BLOCKLIST Blocks all outgoing frames on the links that you listed in the List of Links parameter Passes all the outgoing frames on the links that are not listed An empty list means that all links pass the frames Note If you chose PASS or BLOCK skip the List of Links parameter Outgoing NetBIOS Name List of LInks Range 1 5 to 36 Default The individual numbers correspond to the links ...

Page 88: ...hows the detailed statistics screen that includes counts of the number of NetBIOS broadcasts filtered on the link Figure 42 Detailed Bridge Link Statistics For More Details Refer to the Detailed Bridge Link Statistics section on page 127 Node Address Date Time Detailed Bridge Link Statistics Bridge Link 01 Page 2 of 2 Filter Discards In Out RIF Error Discards Source MAC Address 0 0 Segment Mismatc...

Page 89: ...tion the packet does not use an EtherType code to distinguish the packet format The LLC DSAP SSAP CTL fields are 0xF0 0xF0 x03 The first byte following the above LLC layer is considered offset 0 of the NetBIOS PDU protocol data unit The two bytes at NetBIOS offset 2 3 are 0xFF and 0xFE NetBIOS frame delimiter Either one of the following is true The NetBIOS command byte at offset 4 is 00 Add_Group_...

Page 90: ...all amount of the bandwidth The automatic version is redundant since PathBuilder S200 series switch has the capability of re autocalling the destination thereby rerouting over another link Manual Spanning Tree Manual Spanning Tree is static and cannot adjust to bridge network topology changes However the process is more straightforward and does not consume network bandwidth no Hello frames are use...

Page 91: ... used by a bridge that notices a topology change to send a notification in the direction of the Root Bridge This occurs only during Automatic spanning tree operation When the Root Bridge finally gets this notification it sets the topology change notification bit in the BPDU that it periodically generates This informs all bridges that there has been a change in topology and that they should expect ...

Page 92: ...orities accordingly to avoid unreasonable performance due to long data paths In fact this responsibility points out a major disadvantage of using a bridge network in a mesh topology instead of a router The spanning tree protocol does not allow the bridges to determine optimal paths and to route frames along them Trying to handle this task manually by configuring bridges and bridge links quickly be...

Page 93: ...ecause of the critical nature of the timers involved the spanning tree topology may become unstable It may become difficult to trace this behavior as the effect might occur only occasionally and only in certain types of traffic patterns Example of a Bridge Network With Spanning Tree Figure 43 shows a bridge network composed of six PathBuilder S200 series switches and five LANs The links that are i...

Page 94: ...nks that are part of the spanning tree In Automatic mode the Root Link is determined by summing path costs from a bridge to the Root Bridge Path costs are configured in the Bridge Link Record If there are multiple paths to the Root Bridge the bridge selects the route with the least cost to the root as the preferred link Root Link All other links associated with the bridge become Designated Links F...

Page 95: ... Returning to the mesh network in Figure 43 look at bridge B3 if the WAN lines are all 19 2 kbps and the links are directly connected with a single SVC hop then their incremental cost for WAN links can be set to STPE Path Cost 3536 Therefore B3 will see messages from other bridge links resulting in the following cost to the root bridge From bridge 1 link 6 root is bridge 1 cost to root 3536 From b...

Page 96: ...the bridge link through Node B should be higher than the cost for the direct link On the other hand if the amount of traffic due to sources other than bridging traffic causes added delay for the direct route or if the direct route has a lower speed it might be better to use the direct route as a backup Therefore one would set the cost for the direct route higher than for the Node B route For the m...

Page 97: ...nfigured to have a higher priority lower Bridge ID than B3 so B4 selects link 7 as its root link The second consideration occurs when two links on the same bridge are receiving messages from the same adjacent bridge and the messages report the same root bridge and the same cost to the root bridge This could occur if there were two links between B3 and B4 The bridge will choose the link with the lo...

Page 98: ...termining the root link In this case the designated link is the link issuing the message that Identifies the root bridge with the lowest numerical bridge ID Has the lowest cost to the root assuming there is a tie in reporting the root bridge Identifies itself with a higher priority ID assuming there is a tie in reporting the root bridge and the cost to the root bridge Has the higher priority link ...

Page 99: ...o principal timers used by the spanning tree protocol for detecting a fault condition When selecting values to configure these two parameters consider the fact that the bridge network is when X 25 WAN circuits are used overlaid onto an underlying network which has its own timers and recovery procedures It is important that the two networks do not interfere with each other s protocols especially wh...

Page 100: ...k that the values are satisfactory for the operational environment The Max Age range of values is 6 to 40 and the default is 20 The Hello Time range of values is 1 to 4 and the default is 2 seconds These values allow the enforcement of timer relationships for any reasonable choice of values The factor of two between Max Age and Hello Time allows one of the hello messages to be lost due to for exam...

Page 101: ...when it does not find the entry in its local station cache Once the bridge has built up its cache by listening for a short period of time it can forward packets directly rather than using high overhead broadcasts The Forward Delay is used twice once to allow the topology to stabilize and during this time to process only spanning tree protocol messages and then again to allow the bridge to learn st...

Page 102: ...ed link B3 will determine B1 as the root bridge Its link 5 is its root link and its link 1 is a designated link B4 will temporarily still see B2 as the root bridge Its link 6 is its root link and its link 1 is a designated link At t 2 x Hello Time there is only one root bridge B1 to issue the spanning tree hello message This message is passed along the tree and at this iteration B4 finally sees B1...

Page 103: ...nge to the network Generally if a bridge based on the automatic spanning tree algorithm notices that a link must be moved to or from a block state moved to or from the spanning tree then the bridge informs the root bridge by means of a special message sent out the root port This message includes a flag that indicates a topological change has occurred The root bridge in turn informs all the bridges...

Page 104: ...an LLC2 session between two SNA end stations attached to separate Token Ring LANs connected by a Wide Area Network WAN Additionally Local Termination provides detailed statistics on LLC2 sessions LT Example For example Figure 48 shows a network where running LLC2 Local Termination at the edge point PathBuilder S24x 26x and 27x switches enables spoofing from one side of the network to the other acr...

Page 105: ...timeouts Figure 49 Before Local Termination Example You can increase timer values to reduce the number of session timeouts experienced on a network but configuring large numbers of stations makes such a solution impractical Moreover it does not solve the problem with keepalives slowing down network traffic After Local Termination The best solution to such network traffic problems is to locally ter...

Page 106: ...T Configuration The cluster controller CC using non PathBuilder S200 series switch bridge 3 in Figure 51 is source route bridged to the FEP The local PathBuilder S200 series switch bridge 1 at the FEP use location tries to locally terminate the session since all frames bearing the MAC address of the FEP are to be spoofed However the non PathBuilder S200 series switch bridged cluster controller wil...

Page 107: ... IEEE802 2 LAN model Its function is to establish maintain and terminate the logical link between adjacent stations in a network LLC Frame Description There are three types of LLC operations LLC2 Frame Description Logical Link Control 2 LLC2 is a connection oriented acknowledged protocol LLC2 requires a connection setup between two LAN devices LLC2 is based on the HDLC protocol and is used to tran...

Page 108: ...ens between Spoofers Local Termination runs a subset of LLC2 protocol between spoofers to ensure that frame traffic reliably passes from one edge point node to another edge point node in your network The subset protocol uses separate timers and retry counts that can be set greater than the LLC protocol timers Intermediate Frames between Spoofers LLC2 LT supports intermediate Token Ring networks be...

Page 109: ...ocal Termination traffic and regular bridge traffic By assigning a separate lower priority to spoofer traffic the regular bridge traffic is queued quicker The extra delay of spoofer traffic does not affect the acknowledgments of frames on the LAN See Configuring Local Termination section on page 106 for details on setting the LLC LT WAN Data Priority parameter record ...

Page 110: ...hese steps to configure bridge parameters to enable Local Termination on a node Step Action 1 Configure the node 2 Configure the ports 3 Configure the route selection table 4 Configure the LAN connection table 5 Configure the Mnemonic Table and PVC Setup table 6 Configure the bridge for Local Termination Go to Configuring the Bridge section on page 106 for details on configuring the bridge table f...

Page 111: ...C LT Profile Table Then Go to the section LLC LT Profile Table Configuration LLC LT Profile Table Configuration appears Step Action continued Result Entry Number Range 1 to 64 stations Default 1 Description Entry number used to reference this table Boot Type N A Local MAC Address Range 00 00 00 00 00 01 to 7F FF FF FF FF FF Default 00 00 00 00 00 80 Description MAC address must match the source MA...

Page 112: ... no profile name is specified then default values are used Boot Type LLC LT Station T1Reply Timer Range 1 to 25 seconds Default 3 Description This Ack timer is used by a station to detect a failure of the remote station to acknowledge an outstanding I frame or supervisory frame with the pole bit set to 1 Boot Type LLC LT WAN Parameters T2 Rx Ack Timer Range 1 to 255 tenths of seconds Default 1 Des...

Page 113: ...defines the number of times an I frame or supervisory frame with pole bits set to 1 will be transmitted due to T1 acknowledgment timeout before the logical link will be declared down inoperative Boot Type LLC LT WAN Parameters N3 ACK Delay Count Range 1 to 15 Default 3 Description The Receive Count is used with T2 to reduce the number of acknowledgments a station generates The receive count is use...

Page 114: ...de Boot LCC LT WAN Data Priority Range HIGH MEDIUM LOW Default HIGH Description Specifies the transmission priority of the LLC LT data Boot Type LLC LT WAN Parameters Entry Number Range 1 to 8 Default 1 Description Entry number used to reference this table record Boot Type N A LCC Profile Name Range 0 to 8 alphanumeric space blanks field Default blank Description Local Term Station Table reference...

Page 115: ...he timer expires the link station immediately sends an acknowledgment for all received frames not yet acknowledged Boot Type Tables and Node Record Ti Inactivity Timer Range 2 to 255 seconds Default 30 Description The Idle Timer is used by a station to detect an inoperative condition of the logical link This timer starts when the link is idle no data to pass and no outstanding acknowledgments When...

Page 116: ...om the remote station while withholding acknowledgment of these frames This reduces the number of acknowledgments generated by a link station When this counter expires the link station immediately sends an acknowledgment for all received frames not yet acknowledged Boot Type Tables and Node Record Tx Window Size Range 1 to 15 Default 7 Description Specifies the maximum number of I frames a station...

Page 117: ...sion records Procedure This procedure describes how to delete LT session configuration records Step Action Result 1 Select Delete Record from the CTP Main menu and press Return The Delete Record menu appears 2 Select Delete Bridge from the Delete Record menu The Delete Bridge menu appears 3 Select LLC LT Station Table Entry Or LLC LT Profile Table Entry Entry number 1 appears 4 Press Return to del...

Page 118: ... 26x and 27x switch The PathBuilder S24x 26x and 27x switch is limited to only one Spanning Tree Entity SPTE per node If you perform automatic spanning tree in a Mixed LAN implementation SPTE may prohibit traffic from passing between LANs by blocking some bridge links to avoid bridge looping You must install Release 4 90 or above operating software on all PathBuilder S24x 26x and 27x switches in y...

Page 119: ...ernet port as bridge link 1 Note The default value for this parameter is 1 This matches this port configuration to a specific bridge link number within the bridging configuration If the bridge link you select is already used a warning message appears but your input is retained in the CMEM 5 At the Router Interface Number parameter type in a number 1 4 to identity the router interface For example y...

Page 120: ... statistics screen displays TB Active or SR Active only IP and IPX Support A PathBuilder S24x 26x and 27x switch performing a Mixed LAN operation supports IP and IPX routing of traffic with no additional configuration needed 9 Type and press Return The record is saved 10 Perform a Bridge Link boot from the Boot menu This enables the bridge link 11 Configure the WAN bridge link to support Transpare...

Page 121: ... Router Interface Number 1 Failure to do so may cause your device to perform continuous resets when you power up the device after reinstalling an earlier release of operating software Sample Application Figure 55 shows a sample application for the Multiple Ethernet LAN feature Figure 55 Example of Multiple Ethernet LAN Limitations The PathBuilder S24x 26x and 27x switch supports only two Ethernet ...

Page 122: ...configuration to a specific bridge link number within the bridging configuration If the bridge link you select is already used a warning message appears but your input is retained in the CMEM 5 At the Router Interface Number parameter type in a number 1 4 to identity the router interface Note The default value for this parameter is 1 This matches this port configuration to a router link number wit...

Page 123: ...ils on Parameters See the PathBuilder S200 Series Basic Protocols for details on Ethernet LAN port parameters for Multiple LAN Ethernet operation 10 Perform a Bridge Link boot from the Boot menu This enables the bridge link Step Action continued Result Description ...

Page 124: ...with the LNM Ring Error Monitor A REM observes collects and analyzes hard error and soft error reports sent by stations on a single ring and assists in fault isolation and correction One or more ring error monitors can reside on a ring If no REMs are on a particular ring it is not possible to monitor errors for that ring One or more REMs can report to a LAN manager A REM has a functional address o...

Page 125: ...1 T0008 16F Release 5 2M LAN Server Subsystem Statistics and Alarms Statistics and status alarm thresholds maintained by the LSS are specific for the IBM LNM and can be accessed by the IBM LNM but not from the CTP ...

Page 126: ...dress Virtual Bridge ID Path Trace Control Functional Address Mask Virtual Port s MAC Address Range 00 00 00 00 00 00 to FE FF FF FF FF FF Default 00 00 00 00 00 00 Description Specifies the MAC address of the virtual LAN port of the virtual ring This value defaults to a universally administered second address that is supplied by 3Com in the TRIM card PROM This PROM address is called the Burned in...

Page 127: ... to the IBM LAN Network Manager Functional Address Mask Range 00000000 to 7FFFFFFF hexadecimal Default 0000001A Description Used to enable or disable the LSS servers and represents a 31 bit map of functions where a specific bit identifies a function such as Configuration Report Server CRS Relevant bits should be set if the node supports these functions Configuration Report Server CRS 00 00 00 10 R...

Page 128: ...g Tree Figure 57 shows the Bridge Statistics Menu screen Figure 57 The Bridge Statistics Menu Screen Node Address Date Time Menu Bridge Statistics Path Main STPE Status Detailed Bridge Link Stats Reset Detailed Bridge Link Stats Bridge Link Filters Status TB Forwarding Table Stats LLC LT Session Summary Stats LLC LT Detailed Session Stats Reset LLC LT Detailed Session Stats ...

Page 129: ...g 128 1 Term Description STPE Control Configured value of STPE Control If STPE is configured for MAN the rest of the parameters are not displayed STPE Bridge ID The value of the bridge ID which is transmitted by the bridge in STPE PDUs Root Bridge ID The root of the spanning tree as determined by the STPE Root Path Cost The cost of the path to the root as seen from this bridge Root Port The bridge...

Page 130: ...to STPE PDUs Learning The STE frames are blocked Learning the topology from STPE PDUs Forwarding The STE frames can be forwarded on this bridge link Priority The value of STPE Priority parameter of the bridge link Path Cost The value of STPE Path Cost parameter of the bridge link A weight that is added to the overall links in a particular Ring to Ring path The path with the lowest cost determines ...

Page 131: ... 0 ARE 0 0 STE 0 4 Frame Totals 0 4 TB Frame Summary Received Transmitted Unicast 0 0 Multicast 0 0 Broadcast 0 0 Frame Totals 0 0 Press any key to continue ESC to exit Node Address Date Time Detailed Bridge Link Statistics Bridge Link 01 Page 2 of 2 TB Frames Discarded link not in Forwarding State Inbound Discards 0 Outbound Discards 0 TB Frames Discarded due to unicast link protect being set Inb...

Page 132: ...PE Control AUTO STPE view of the link s current state is displayed Disabled LAN or WAN connection is inactive Blocking The STE frames are blocked on this Bridge Link Listening The STE frames are blocked Learning the topology from STPE PDUs Forwarding The STE frames can be forwarded on this bridge link Bridge Link Type LAN If Bridge Link number is 1 WAN If Bridge Link number is 5 to 36 Last Stat Re...

Page 133: ...AC Address Filter discard due to source MAC Address match in filter table Dest MAC Address Filter discard due to destination MAC Address match in filter table Protocol Filtered Filter discard due to Protocol type MAC Address match in filter table Total Filter Discards The total number of frame discards due to filter action RIF Error Discards The number of frames that were discarded due to incorrec...

Page 134: ...of 1 Bridge Link Filter Action MAC Address Block Protocol Pass Active Filters MAC Address Source In Source Out Dest In Dest Out 080AB546787C PASS BLOCK PASS PASS 01287D46787C BLOCK BLOCK BLOCK PASS Protocol Class Value Incoming Outgoing DSAP 8F PASS PASS SNAP 0000010808 BLOCK BLOCK Press any key to continue ESC to exit Term Description Bridge Link Filter Action MAC Address This field reports on th...

Page 135: ... Value PASS or BLOCK from the MAC Filter Table Action to be taken on outbound frame for the indicated MAC Destination address Active Filters Protocol Class Protocol Class Value DSAP or SNAP of Protocol Class parameter of a Protocol Filter Table Value Represents the value of the Protocol parameter of a Protocol Filter Table This value can be 1 byte DSAP or 5 bytes SNAP depending upon which type of ...

Page 136: ...Link Number Status 03 00 FF FF FF FF Other 08 00 3E 00 1B 96 Other FF FF FF FF FF FF Other Press any key to continue ESC to exit Term Description Learned Entry Discards The number of Learned Address List entries that have been discarded due to lack of room in the forwarding database the database size had been at its maximum allowed when the entry was learned Learned Entries The total number of ent...

Page 137: ...arding database displayed by the status statistics screen Bridge Link Number Indicates the corresponding bridge link number used to forward a frame with the given MAC Address Status Indicates how the forwarding entry was learned CONF This entry was learned from the permanent learned station address stored in CMEM LEARN This entry was learned from the received frames on bridge links Term continued ...

Page 138: ...3 Node Address Date Time Detailed Bridge Link Statistics Bridge Link 01 Page 2 of 2 TB Frames Discarded link not in Forwarding State Inbound Discards 0 Outbound Discards 0 TB Frames Discarded due to unicast link protect being set Inbound Discards 0 Outbound Discards 0 TB Frames Discarded due to multicast link protect being set Inbound Discards 0 Outbound Discards 0 Filter Discards In Out RIF Error...

Page 139: ...counter is incremented when the inbound frame on a Bridge Link is not forwarded because of MAC Address Table filtering on the source address OUT This counter is incremented when the outbound frame on a Bridge Link is not forwarded because of MAC Address Table filtering on the source address Destination MAC Address IN This counter is incremented when the inbound frame on a Bridge Link is not forwar...

Page 140: ...ction Statistics Path Main 5 9 LAN Connection Stats LAN Connection Summary Stats Reset LAN Connection Stats Node Address Date Time Detailed LAN Connection Statistics LCON 5 Page 1 of 2 Last Statistics Reset Date Time Transmit Data Summary Number of Packets Transmitted 0 Average Transmit Packet Size 0 Current Transmit Queue Depth 0 Maximum Transmit Queue Depth 0 at Date Time Receive Data Summary Nu...

Page 141: ...ry Connection Type SVC Connection State Improper Config Forwarders Connected Remote Address Number of auto call attempts 0 Last clear cause code 0 Cleared by other end Last clear diagnostic code 0 No more information Packet Summary Transmit Receive Data 0 0 Call Request 0 0 Call Accept 0 0 Clear Request 0 0 Clear Confirm 0 0 Reset Request 0 0 Reset Confirm 0 0 Press any key to continue ESC to exit...

Page 142: ...ongested Forwarders Connected Specifies which forwarders are currently connected to this LAN Connection Source Route Spanning Tree Remote Address Specifies the called address of the remote WAN Adapter LAN Connection for connected SVCs The possible states are Blank for PVCs blank for disconnected SVCs No Mnemonic for autocall SVCs whose mnemonic does not exist in the Mnemonic Table Max Attempts for...

Page 143: ...tistics reset Resetting the statistics does not clear the last call information from the detailed port statistics screen This information is cleared only on a node boot Transmit Data Summary This field provides information on the transmission of packets and those awaiting transmission to the WAN Totals are provided for the number of packets transmitted the average transmitted packet size in bytes ...

Page 144: ...ription LAN Connection Specifies the LAN Connection entry number and current state of a configured LAN Connection The possible states are Not Properly Configured Not Connected Calling Waiting for Call Connected Waiting for Clear Confirmation Disabled Bridge Link Specifies the WAN Bridge Link number associated with this LAN connection The possible current states of the WAN Bridge Link are Not Appli...

Page 145: ...00 04 A1 F4 Up 6 2 10 00 5A E1 A2 C4 F4 10 00 7C 00 C4 C2 F4 Up 7 2 10 00 5A E1 A2 C4 F4 10 00 7C 00 04 E5 F4 Up Press any key to continue ESC to exit Heading Description Session Session number assigned between the MAC addresses Maximum number of sessions supported is 64 Stn Refers to the entry number assigned to the LT session for the local MAC address during configuration Maximum number of stati...

Page 146: ...dicates the session between the local and remote MAC addresses UP MAC addresses are communicating using Local Termination DOWN MAC addresses are not communicating Session is the process of coming up or going down Heading continued Description ...

Page 147: ... 0021 0010 Last Statistics Reset Date Time Local Station Session Summary TX Window 7 Protocol State 4 Characters In 3740798 Characters Out 36107 Frame Type In Out Frame Type In Out Info 17682 3980 UI 0 RR 4018 6827 TEST 0 RNR 0 1 XID 1 REJ 0 0 DISC 0 0 SABME 1 0 DM 0 0 UA 0 1 FRMR 0 0 Frames received out of sequence 0 Bad Frames received 0 Frames dropped 0 Press any key to continue ESC to exit Nod...

Page 148: ...values Local MAC MAC address of the local device Remote MAC MAC address of the remote device Local SAP SAP being used by local device Remote SAP SAP being used by the remote device WAN Queue Depth Indicates the number of packets queued for transmission to the WAN or waiting for acknowledgment from the remote spoofer LAN Queue Depth Indicates the number of packets queued for transmission to the LAN...

Page 149: ...or transmitted by the local spoofer SABME Number of SABME frames received or transmitted by the local spoofer from or to the local device UA Number of UA frames received or transmitted by the local spoofer to or from local device UI Number of UI frames received by the local spoofer from the local device TEST Number of Test frames received by the local spoofer from the local device XID Number of XI...

Page 150: ...e spoofer SABME Number of SABME frames received or transmitted by the local spoofer from or to the remote spoofer UA Number of Unnumbered Acknowledgment UA frames received or transmitted by the local spoofer to or from the remote spoofer UI Number of Unnumbered Information UI frames received by the local spoofer from the remote spoofer TEST Number of Test frames received by the local spoofer from ...

Page 151: ...e port to be reset For TR port Number 55 all the statistical counters are set to zero Reset Bridge Link Stats This command prompts you to enter the number of the bridge link to be reset All the statistical counters of the selected bridge link are set to zero Reset All Stats This command resets all the statistics of the PathBuilder S200 series switch This includes statistics of the TR port and all ...

Page 152: ...148 Bridging Bridge Statistics ...

Page 153: ...e latest networking information on the 3Com Corporation World Wide Web site by entering the URL into your Internet browser http www 3com com This service provides access to online support information such as technical documentation and software library as well as support options ranging from technical education to maintenance and professional services 3Com FTP Site Download drivers patches and sof...

Page 154: ...ance is required contact your network supplier Many suppliers are authorized 3Com service partners who are qualified to provide a variety of services including network planning installation hardware maintenance application training and support services When you contact your network supplier for assistance have the following information ready Product model name part number and serial number A list ...

Page 155: ...a Indonesia Japan Malaysia New Zealand Pakistan Philippines 1 800 678 515 800 933 486 61 2 9937 5085 001 800 61 009 0031 61 6439 1800 801 777 0800 446 398 61 2 9937 5085 1235 61 266 2602 P R of China Singapore S Korea From anywhere in S Korea From Seoul Taiwan R O C Thailand 10800 61 00137 or 021 6350 1590 800 6161 463 82 2 3455 6455 00798 611 2230 0080 611 261 001 800 611 2000 Europe From anywher...

Page 156: ...dle East 011 44 1442 435860 011 44 1442 435718 From the following European countries you may call the toll free numbers select option 2 and then option 2 Austria Belgium Denmark Finland France Germany Hungary Ireland Israel Italy Netherlands Norway Poland Portugal South Africa Spain Sweden Switzerland U K 06 607468 0800 71429 800 17309 0800 113153 0800 917959 0130 821502 00800 12813 1800553117 177...

Page 157: ...ing Protocol Link Action 73 Protocol Type 72 Protocol Value 72 Bridge Statistics 124 Bridging connecting LANs via X 25 link 15 connecting multiple Token Ring LANs 15 example of SVC arrangement 16 frame handling 39 transit time 36 Broadcast function 57 bulletin board service A 2 Burroughs Poll Select 2 C Codex Proprietary Protocol ID defining 22 Configuration bridge parameters 106 improper configur...

Page 158: ...136 LAN Connection Subaddress defining 22 LAN Connection Table 31 configuring 31 LAN connections example 42 LAN Forwarder Type 32 LAN links 17 LAN Server Subsystem Configuration Report Server 120 Ring Error Monitor 120 Ring Parameter Server 120 See LSS 120 LAN Server Subsystem LSS 120 List of Links parameter function 59 Protocol filtering description 75 LLC1 TEST frame 42 LLC2 recovery procedures ...

Page 159: ...s deleting 113 REM 120 Reset Bridge statistics 147 returning products for repair A 4 RIF 42 Ring Error Monitor 120 Ring Parameter Server see RPS Root bridge link 87 Routing Info Indicator bit description 43 Routing Information Field 39 42 function 43 remote ring number 39 Routing Information Present bit 39 Routing TEST frame Routing Type field 46 RPS 120 S SDLC 2 Sessions maximum number of LT sess...

Page 160: ...ss 67 MAC Address Filter Action 28 Outgoing Destination Address Link Action 69 Outgoing Source Address Link Action 68 Protocol Filter Action 29 STPE Control 23 TR Records and Parameters 21 Traffic Priority described 105 Translational Bridging 2 37 configuration example 37 38 configuration guidelines 37 Transparent 2 Transparent bridge aging 52 filters 54 learning 48 Multicast Protect flag 55 Unica...

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