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Bercut-MMT

Ethernet 10/100 and Gigabit Ethernet Analysis

Operation Manual

1.2.7, 2009

Metrotek

Summary of Contents for Bercut-MMT

Page 1: ...Bercut MMT Ethernet 10 100 and Gigabit Ethernet Analysis Operation Manual 1 2 7 2009 Metrotek ...

Page 2: ...roduced in any form or by any means without the express written permission of Metrotek Metrotek retains the right to make changes to the hardware software of 10 100 1000 Mbit s Ethernet Networks Testing Module and to this document at any time without notice ...

Page 3: ...election 14 3 3 Connection to Network Interfaces 14 3 4 Network Interfaces State Indication 14 4 RFC 2544 Parameters Configuration 17 4 1 Topology 19 4 2 Frame 20 4 3 Throughput 24 4 4 Latency 25 4 4 1 Theoretical Maximum Throughput Value 26 4 5 Frame Loss 27 4 6 Back to Back 28 5 RFC 2544 Measurements 29 5 1 Throughput 31 5 1 1 Plot 32 5 1 2 Table 33 5 2 Latency 33 5 2 1 Plot 34 5 2 2 Table 35 5 ...

Page 4: ... SNMP Protocol 53 8 1 SNMP Data Display 53 8 1 1 Advanced Settings Dialogue 54 9 PPPoE Protocol 57 9 1 PPPoE Connection Display 57 10 Network Interfaces Information 59 10 1 Interface Status 59 10 2 SFP Information 60 10 3 Cable test 61 11 Loopback 63 11 1 Loopback Modes in Ethernet Networks 63 11 1 1 First Layer Loopback 63 11 1 2 Second Layer Loopback 63 11 1 3 Third Layer Loopback 64 11 2 Loopba...

Page 5: ...d Priorities 73 B 1 VLAN Tags 73 B 2 Type of Service 73 C System Technical Specifications 75 D Glossary 77 E Technical support 81 E 1 Contact Information 81 F Troubleshooting 83 Bibliography 85 Bercut MMT Ethernet Networks Analysis ...

Page 6: ...6 CONTENTS Bercut MMT Ethernet Networks Analysis ...

Page 7: ... view of the device Figure 1 1 External view The Bercut MMT device consists of the system unit and two pluggable modules cards1 that provide an interface to such testing objects as PCM E1 streams data transmission interfaces Datacom or Gigabit Ethernet The System Unit provides for the basic device functionality i e control of Bercut MMT platform components an interface to peripheral devices power ...

Page 8: ... pluggable cards have different sets of hardware interfaces and pro grammable options Each card has a unique serial number and provides in formation about a manufacturer types of interfaces allowed measurement options etc 1 2 Documentation Set Depending on the ordered options the following operations guides are deliv ered with the device Bercut MMT Telecommunication Networks Analyzer Universal Pla...

Page 9: ...r traffic redirection should be implemented loopback description can be found in section 11 page 73 RFC 2544 parameters basic configuration should be performed accord ing to section 4 page 17 interface configuration IP and MAC ad dresses frame size configuration adding VLAN tags frame priority load and test duration setting for throughput frame loss level latency back to back measurements to measu...

Page 10: ...tions may be a problem in some cases because for such protocols as VoIP latency deviations or its increase may result in lower voice transmission quality Back to back marginal load measurements This test is transmission of frames of maximum length at maximum speed which corresponds to minimal possible gap between frames during certain time period starting from idle state Test result is quantity of...

Page 11: ...2 3 B4 GBE Ethernet Network Analysis Card 11 The B4 GBE card layout is shown at Figure 2 1 Figure 2 1 B4 GBE Card Bercut MMT Ethernet Networks Analysis ...

Page 12: ...12 General Information Bercut MMT Ethernet Networks Analysis ...

Page 13: ... 3 1 Device Connection Diagrams Port 0 DUT NUT Loopback Figure 3 1 Connection Diagram 1 Port 0 Port 1 DUT NUT Figure 3 2 Connection Diagram 2 Port 0 DUT NUT Port 1 Figure 3 3 Connection Diagram 3 Bercut MMT Ethernet Networks Analysis ...

Page 14: ...e Update utility for detailed description of operation mode configuration for pluggable modules refer to Bercut MMT operations manual Telecommunication Systems Universal Analyzer Plat form 3 3 Connection device to Network Interfaces Install the B4 GBE card according to description in Operations Manual Install SFP modules in the card interface ports up to click 1 Connect device to the network equip...

Page 15: ...n is established the column shows established link rate Testing state TEST green colour means RFC 2544 measurement mode is active frame transmission and reception is active LB1 green colour means loopback mode is active indicator corresponds to the loopback layer LB1 LB2 LB3 RX transmission state Is green when a frame is sent TX reception state Is green when a frame is received Bercut MMT Ethernet...

Page 16: ...16 Staring Up Bercut MMT Ethernet Networks Analysis ...

Page 17: ...quence O Menu Ethernet Testing Ethernet testing config Application main window layout is shown at Figure 4 1 Figure 4 1 Ethernet RFC2544 Parameters The Ethernet RFC2544 Parameters application window contains the following tabs Topology to choose source interface and destination interface from available in the list Note in case source and destination interfaces are not con figured there are no IP a...

Page 18: ...oss level measurement parame ters Back to Back configuration of maximum load measurement pa rameters Each of the mentioned application tabs is described in details in the fol lowing sections of this chapter Above all tabs there is Apply button When it is pressed previously configured parameters are activated To display F1 F8 functional keys designation refer to Figure 4 2 it is necessary to press ...

Page 19: ...nterface and des tination interface Available local and or remote interfaces Bercut MMT devices are listed in the drop down lists When interfaces for testing are selected reference information IP and MAC addresses of corresponding in terfaces is displayed below the chosen fields To save current configuration of this tab it is necessary to press the Ap ply key or F7 functional key with the same fun...

Page 20: ...at least one value must be chosen Ethernet this tab contains fields to enter source and destination MAC addresses that will be inserted in the corresponding fields of the test packets The Automatically tab is used to insert MAC addresses of source and destination interfaces that are chosen in the Topology tab MAC addresses may be configured using virtual keyboard Virtual key board refer to Figure ...

Page 21: ...ficant when processing in network device is carried on Priority and traffic type mapping according to IEEE 802 1Q are shown at Figure 4 5 and are described in Table B 1 of Annex B page 73 Figure 4 5 The VLAN Tags tab layout VLAN ID a 12 bit VLAN identification is a number from 0 to 4095 uniquely identifies the network a frame belongs to VLAN ID zero value shows this given frame carries no informat...

Page 22: ...e of IP datagram is used to avoid endless circulation of packets in the network a number from 0 to 255 should be entered Figure 4 6 The MPLS labels tab layout Figure 4 7 The IP tab layout IP this tab consists of a number of fields that have to be edited in order to generate outgoing traffic properly Source IP is a field to enter sender s IP address is populated with virtual keyboard that is displa...

Page 23: ...ets sender can set any value in this field compliant to RFC 1349 in particular values shown at Figure 4 9 and described in Table B 3 of Annex B page 73 are possible Figure 4 9 Type of Service UDP with this tab a port is configured to send and receive data for a protocol selected under IP tab Figure 4 10 The UDP tab layout TCP with this tab a port is configured to send and receive data for a protoc...

Page 24: ...mbers hexadecimal representation in the form of 0x0001 0x0002 etc Meander a sequence of alternating zeroes and ones Below all tabs there is a coloured scheme that corresponds to packet struc ture and includes all fields comprising the datagram 4 3 Throughput Figure 4 12 Throughput Measurements Configuration Enable this test is a flag that turns throughput measurement on or off the F2 functional ke...

Page 25: ...en max imum and minimum load values at current iteration is lower than a certain predefined Precision value Values are measured in percents of maximum connection throughput Minimum resolution value corresponds to maximum test accuracy but this increases measurements duration Duration sec time period of one measurement iteration for each frame size selected in the general frame size configuration n...

Page 26: ...t Throughput test in this case Latency values will be calculated for determined throughput or define desirable frames transmission rate Frame transmission rate values if configured manually should not exceed theoretical maximum throughput value for cur rent settings 4 4 1 Theoretical Maximum Throughput Value Theoretical maximum throughput value is calculated using minimal values of the following p...

Page 27: ...or off the F2 functional key has the same meaning Load these are fields that allow to configure load change parameters at loss level measurement minimal Min maximal Max load values and Step parameter Step is a value by which a load is decreased on each iteration maximum step is 10 Values are measured in percents of maximum connection throughput Duration time period of one measurement iteration for...

Page 28: ...that turns Back to Back maximum load measurement on or off F2 functional key has the same meaning Initial frame count frames the starting length of transmitted sequence Step frames is a step of frame quantity sequence length chang ing Trials quantity of measurements for each frame size configured Bercut MMT Ethernet Networks Analysis ...

Page 29: ...t testing The application window is shown at Figure 5 1 Figure 5 1 Measurements Window The window consists of the following elements 1 Dynamic list of measurements Names colour is changed during mea surements process Initially all tests names are unavailable and are of grey colour The name of a test currently executed is highlighted by blue completed test is shown in black 2 Execution indication t...

Page 30: ...t Abort start and stop testing process corresponds to F6 functional key To stop the testing process press the Abort button In case the testing process is not aborted system will automatically stop its execution after all necessary measurements are completed Save save obtained results as a file corresponds to F7 functional key Save for more details refer to Par 5 5 1 page 40 Note if current measure...

Page 31: ... why this tab for each test is not discussed in this Manual 5 1 Throughput Throughput measurements provide maximum rate value at which there is no loss of frames transiting the system being tested Using previously obtained maximum rate value it is possible to determine available channel bandwidth Bercut MMT Ethernet Networks Analysis ...

Page 32: ...gure 5 3 Throughput Test Results Plot This diagram shows measured and theoretical throughput values fps for each data packet set in the configuration Theoretical values are calculated for full 100 load Bercut MMT Ethernet Networks Analysis ...

Page 33: ...s quantity of packets transmitted Tx and received Rx and quantity of lost frames 5 2 Latency It is time that a frame needs to go through network and return back at network elements with buffering This parameter allows to measure a time period that starts from a moment when last bit of outgoing frame leaves transmitting side passes through DUT NUT and finishes at a moment when first bit of a frame ...

Page 34: ...Measurements 5 2 1 Plot Figure 5 5 Latency Test Results Plot The diagram shows measured minimum maximum average delay value in mi croseconds for each data frame size configured Bercut MMT Ethernet Networks Analysis ...

Page 35: ...le shows measured throughput value and average minimum maximum delay value in microseconds for each frame size configured The Distr dis tribution column shows by what value on average all delays differ from average value in microseconds Bercut MMT Ethernet Networks Analysis ...

Page 36: ...f LoT indicates that DUT is able to support the current frames flow The diagram shows delay changing during test execution Horizontal axis corresponds to the last 60 seconds of a test 5 3 Frame Loss Frame loss measurement allows to calculate percent of frames that were not transmitted by object under testing network or device at constant load due to the lack of hardware resources This measurement ...

Page 37: ... in dependency upon normalized value in equal to ratio of input load to theoretical maximum throughput of equipment under testing Buttons at the left and right diagram sides are used to display frame size and its corresponding curve colour These buttons allow to view the diagrams one by one or in together Bercut MMT Ethernet Networks Analysis ...

Page 38: ...ible gap between frames during certain time period starting from idle state The result of the test is quantity of frames at most durable packet trans mission at which a device under testing or network does not loose any frame This means that for equipment that supports transmission of any quantity of frames of certain size at maximum rate testing will continue forever and result will not be obtain...

Page 39: ...9 5 4 1 Plot Figure 5 10 Back To Back Test Results Plot The diagram shows measured minimum maximum average quantity of frames transmitted without loss for each frame size configured Bercut MMT Ethernet Networks Analysis ...

Page 40: ... Table tab are saved Information about measurements execution from the Details tab is not saved Results stored in CSV format can be viewed and edited on PC with any application that support electronic tables Results stored in XML format can be loaded for review into Ether net RFC2544 test application The Save button is used to save current measurement results On pressing it a dialogue window appea...

Page 41: ...and to cancel an action 5 5 2 Previously Saved Results Display Previously saved measurements loading function is available in case there are no active tests of Ethernet test RFC2544 application The Load button or F8 functional key is used to open measurement results loading window shown at Figure 5 13 Bercut MMT Ethernet Networks Analysis ...

Page 42: ...rnet test RFC2544 application allows to re view only the results that have been saved in XML format The Name field of dialogue window allows to select a name of results file of interest The window has OK button to load and to cancel an action Bercut MMT Ethernet Networks Analysis ...

Page 43: ...ecking data transmission route determination data transmission channel availability checking To activate this application the IP tools program is used refer to Fig ure 6 1 O Menu Ethernet Testing IP tools Figure 6 1 Navigation to the IP tools application Note all entered IP addresses and or node names are stored in the drop down lists of corresponding tabs after tests execution Bercut MMT Ethernet...

Page 44: ...on The Number of ping field is used to configure the required quantity of ICMP protocol requests For more accuracy more requests should be configured The minimal value sufficient to check the connection is 1 If this field is left blank testing will be performed until Stop button or F6 functional key is pressed Test execution starts on pressing the Start button or F6 functional key Ping statistics ...

Page 45: ...raceroute Parameters Configuration Destination target node IP address or name Interface name of the interface that will be used for data transmis sion reception Default interface is defined by routing configuration To change an interface name the line should be selected from the drop down list or F1 functional key should be used Test execution starts on pressing the Start button or F6 functional k...

Page 46: ... Figure 6 4 This table generates device lists based on subnetworks routers and is updated periodically Figure 6 4 ARP Parameters Configuration The ARP table is loaded on pressing the Start button or F6 functional key The all entries flag F2 functional key has the same designation is used to display network routers and their addresses The Destination field value is ignored To find certain IP addres...

Page 47: ...m execution is completed on ARP table update in the ARP tab the information about the device in question will be displayed Test configuration is performed by filling out following fields Destination target node IP address for ARP request Number of arping is used to configure a certain quantity of ARP requests Interface displays interface name to work with Default interface is defined by routing co...

Page 48: ... URL field should be populated with URL of the needed resource1 Test result is displayed in two information blocks first has node name its IP address and port last two dig its separated by colon from IP address Below the first block the second one is located that contains downloaded page format and downloaded amount in percent as shown at Figure 6 6 Figure 6 6 Results of connection using ftp http ...

Page 49: ...ram should be used O Menu Ethernet Testing IPX Analysis 7 1 IPX Protocol Analysis The IPX Analysis program collects IPX packets on the selected interface and displays the contents of their headers first 64 bytes at the device screen Screen layout is shown at Figure 7 1 Figure 7 1 IPX Protocol Analysis Program Program configuration window has the following elements Start Stop testing process start ...

Page 50: ... bytes of IPX packet header and data Figure 7 3 Detailed view of collected Packets count is a field to configure IPX packets quantity infinite is a flag to turn infinite collection of packets on or off is interrupted by pressing the Start Stop button In order to work with the program it is necessary to select an interface where IPX packets are to be collected select detailed view mode if necessary...

Page 51: ... collected Note on pressing the Start button any configuration changes are impos sible after packets collection is finished fields become available for configuring again IPX packets analysis results are put into information table with time of packet reception packet sender MAC address packet recipient MAC address protocol type etc Bercut MMT Ethernet Networks Analysis ...

Page 52: ...52 IPX Protocol Bercut MMT Ethernet Networks Analysis ...

Page 53: ...hanges To make this protocol operational an agent and manage ment system that collects information about agents status are needed 8 1 SNMP Data Display The SNMP program O Menu Ethernet Testing SNMP browser collects SNMP statistics from the specified agent Application window layout is presented at Figure 8 1 Figure 8 1 SNMP Program Bercut MMT Ethernet Networks Analysis ...

Page 54: ...Protocol SNMP protocol version selection available options are v1 v2c v3 Advanced advanced settings dialogue Current MIB current MIB file1 that is selected in the advanced settings dialogue Start data collection start 8 1 1 Advanced Settings Dialogue Figure 8 2 SNMP Program Advanced Settings Pressing the Advanced button allows to configure Security name user name for SNMP protocol versions v2c v3 ...

Page 55: ... field should be populated with user name select needed MIB file to terminate working with application and configuration saving press the OK button or selected file will be shown in Current MIB field of the main application window to execute testing press the Start button When data collection has been started application screen displays Wait please message When data collection is completed the Sta...

Page 56: ...56 SNMP Protocol Bercut MMT Ethernet Networks Analysis ...

Page 57: ...t and server used for authentication virtual channel creation and subsequent data exchange 9 1 PPPoE Connection Display The PPPoE program O Menu Ethernet Testing PPP performs PPPoE connection testing for specified server The Bercut MMT device acts as a client Window layout is presented at the figure Figure 9 1 PPP Program Bercut MMT Ethernet Networks Analysis ...

Page 58: ...HAP or CHAP bidir Auth Type drop down list enter server name in the Server Name field enter PPPoE service name at the server in the Service Name field enter user name in the user name field enter password in the password field enter local system password in the Local pass field2 to execute testing press the Start button When PPPoE connection is being setup the Status field shows Connec tion in pro...

Page 59: ...Testing Net Interfaces Information SFP module information includes following parameters manufacturer name model operation modes supported Copper cable diagnostics supports standard faults detection cable cut short circuit polarity twisted pairs crossing detection and also cable length measuring To retrieve network interfaces data it is necessary to connect SFP mod ule and to select interface from ...

Page 60: ... Auto negotiation state of auto negotiation mode Link detected presence of connection for selected interface Note the table refreshes periodically and in case SFP module is not present applicable message is displayed For interfaces used to connect to local area network eth0 eth1 connec tion rate will be 10 100 Mbit s Ports of the pluggable cards with installed SFP modules purchased together with t...

Page 61: ...l name of SFP module supported modes modes of SFP module operation supported 10 3 Cable test Copper cable diagnostics is performed to obtain main parameters of interface under testing Testing starts on pressing the Run cable test button Test results are displayed in the form of a table Table columns contain information about each pair of cable wires Bercut MMT Ethernet Networks Analysis ...

Page 62: ...s value range is from 0 to 255 field is valid for short and open states only in other modes it is n a skew difference in transmission time over the longest and the short est cable pair phase distortion value range of values is from 0 to 15 ns polarity twisted pairs polarity can be negative positive cross twisted pairs crossed connection MDI MDI X this field is valid for 1000BASE T mode only and ca...

Page 63: ...all incoming traffic including packets with errors1 are redirected back without any changes Figure 11 1 Figure 11 1 First Layer Loopback Connection 11 1 2 Second Layer Loopback Incoming traffic is redirected back at the link layer defective packets are not transmitted with this sender and recipient MAC addresses are switched VLAN tags can be replaced other user defined MAC addresses may be inserte...

Page 64: ... switching of MAC addresses sender and recipient IP addresses are switched another user defined MAC and IP addresses can be inserted also ToS and VLAN tags can be changed Figure 11 3 Third Layer Loopback Connection For One Port 11 2 Loopback Configuration To activate this application the Loopback Configuration program can be used refer to Figure 11 4 page 65 through an access to O Menu Ethernet Te...

Page 65: ...tion field to implement loopback Figure 11 5 Interface selection for testing Note network interface with the loopback at any layer is un available for data packets transmission reception This means that conducting RFC 2544 testing IP testing cable testing is not possible Loopback layer selection field Bercut MMT Ethernet Networks Analysis ...

Page 66: ...ed on pressing with a stylus to the MAC address field and has symbols characters and digits necessary to enter the MAC address Figure 11 7 Virtual Keyboard to Enter MAC Address Note in case the selected loopback layer is Layer 2 the replace IP with field and TOS Settings menu are deactivated The VLAN Settings menu has Tag flags a mark within Ethernet packet structure When a flag is set VLAN ID and...

Page 67: ...rity set a priority which a frame will be tagged with is considered on processing in the network device Priority and traffic type mapping according to IEEE 802 1Q is presented in Table B 1 of Annex B page 73 If Layer 3 is selected as loopback layer both source and destination MAC addresses and IP addresses will be switched To change MAC and IP addresses it is necessary to set corresponding flags F...

Page 68: ...rected IP packets for detailed information about possible values refer to Table B 2 and B 3 Annex B page 73 ToS Precedence refer to Figure 11 10 ToS Value Figure 11 10 ToS Precedence Selection Traffic loopback starts on pressing the Start button or F7 functional key and is active until the Stop button is pressed Bercut MMT Ethernet Networks Analysis ...

Page 69: ...ings Connection manager Figure A 1 Connection Setup The Login field should be populated with the user name that is registered at the remote device Figure A 1 The Host field should be populated with IP address host or remote Bercut MMT name hostname Connection setup is performed by pressing the Connect button When connection with remote Bercut MMT is established for the first time for specified use...

Page 70: ...a line similar to this one user 192 168 222 2051 Figure A 3 will appear Otherwise a notification will appear with possible reasons of connection failure List of active con nections is presented in Annex 4 1 Figure A 3 Active Connections 1Actual view of active connection will differ from this example it depends on user connection parameters user name and IP address Bercut MMT Ethernet Networks Anal...

Page 71: ...A 2 Parameters Configuration After connection setup described in the previous paragraph it is necessary to configure connection parameters as stated in section 4 RFC 2544 Parameters Configuration Bercut MMT Ethernet Networks Analysis ...

Page 72: ...72 Remote Testing Bercut MMT Ethernet Networks Analysis ...

Page 73: ...or delay sensitive traffic such as video and voice Traffic priorities from 3 to 1 are used for different tasks from streaming applications to FTP traffic that is able to overcome possible losses Class 0 best effort delivery rate is assigned to a traffic with lowest priority and is used when no other class is assigned 9 B 2 Type of Service According to RFC 791 eight frame priority values are suppor...

Page 74: ...elivery time from source network device to destination waiting time is most critical and has to be minimal 0100 Maximize throughput Maximum throughput Denotes a packet should be redirected through a channel with maximum throughput 0010 Maximize reliability Maximum reliability Is used when it is important to be sure that data will reach destination without retransmission 0001 Minimize monetary cost...

Page 75: ...s 800x480 pixels 65536 colours sensor panel Keyboard cursor control numeric and functional keys Computer connection in terface RS 232 Ethernet 10 100 BaseT USB client and USB host Power voltage 9 15 VDC input current not more than 3A Batteries Two Ni Mh batteries with nominal voltage of 7 2 V and capacity of 4500 mAh each Batter ies are replaced by manufacturer AC adapter 100 240V 50 60Hz input cu...

Page 76: ...eck Automatic check with configurable constraints and maximum transmission rate Throughput latency frame loss back to back testing Frame size 64 128 256 512 1024 1280 and 1518 bytes IP utilities Ping traceroute ARP arping ftp http Loopback implementation At physical PHY link MAC and network IP layers with VLAN support and fields change capability Cable testing Copper cable testing for open circuit...

Page 77: ...col that converts IP addresses network level addresses to MAC addresses link level addresses in TCP IP networks It is defined in RFC 826 Auto Negotiation the auto negotiation function allows devices adapters and hubs to automatically adjust to the communication rate in the network DUT Device Under Test Ethernet Local area networks implementation technology Is defined in IEEE standard group 802 3 F...

Page 78: ...ission in the unified network based on TCP IP protocol Each datagram has source and destina tion addresses and data IP network In this manual IP network is treated as network that includes devices working at link and network levels such as network switch router LoT Latency over Time Delay distribution in time MAC address Media Access Control address A unique identification that is used to address ...

Page 79: ...ork nodes Total time needed to transmit a packet over network from sender to final recipient and to send it back to sender SSH Secure SHell An application level network protocol that enables remote control of operations system and file transfer TCP Transmission Control Protocol A standard transport level protocol member of the TCP IP protocols family that provides for reliable duplex flow data tra...

Page 80: ... computer net work Sends data directly to recipient Network hub A device used for joining of several nodes of computer network All devices connected to the hub ports receive same information Network Layer Provides for route determination for data transmission Is responsi ble for logical to physical addresses and names mapping for shortest routes determination for switching and routing network faul...

Page 81: ...item Bercut MMT Device Information O menu Config uring Bercut MMT Information and consist of the following infor mation device serial number also present on the rear panel version pluggable modules information Note prior to application to the technical support service it is recommended to update the firmware version of the device and to check its operability again E 1 Contact Information Metrotek ...

Page 82: ...82 Technical support Bercut MMT Ethernet Networks Analysis ...

Page 83: ...ts Fault main indication Possible reason Fault clearing method Connection loss Incorrect connection of a cable to the device Check connected cable integrity and insert it again into the connector up to click Bercut MMT Ethernet Networks Analysis ...

Page 84: ...84 Troubleshooting Bercut MMT Ethernet Networks Analysis ...

Page 85: ...6 materials http tools ietf org html rfc2616 6 FTP RFC2228 materials http tools ietf org html rfc2228 7 Ssh reference handbook http www openssh org 8 Cooperation Agreement for Small Form Factor Pluggable Transceivers http schelto com SFP 9 IEEE Std 802 1Q IEEE Standart for Local and metropolitan area net works Virtual Bridged Local Area Networks 10 RFC 791 Postel J Internet Protocol DARPA Septembe...

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