background image

126

Network Design and Engineering Guide

2010-10-26

Data Networking

SkyWAN

® 

Frame Relay Networking Features

4.3.2

Basic Frame Relay Services

Basic Frame Relay is supported according to the Frame Relay Forum standards FRF 1.2 (UNI)
and FRF 2.2 (NNI). Frame Relay Connectivity is based on the configuration of Permanent Vir-
tual Circuits (PVC) which logically link serial data ports of 

Sky

WAN

®

 IDUs across the satellite

network. 

Up to 300 PVCs can be defined on each serial port. Each PVC is locally identified on a serial
port by its local Data Link Connection Identifier (DLCI). The configured PVCs allow attached
Frame Relay Access Devices to exchange data with remote devices via the 

Sky

WAN

®

 Frame

Relay network. 

For each unicast PVC the following parameters have to be specified in the FR circuit table:
-

Local serial port number

-

Local DLCI number

-

Remote IDU SLL address

-

Remote IDU serial port number

-

Remote DLCI number

This PVC definition is by nature unidirectional. For a bidirectional PVC a matching entry has to
be defined in the circuit table of the remote IDU. 

A Frame Relay connection in a 

Sky

WAN

®

 network is always a direct single hop connection be-

tween the IDUs. Double hop connectivity via an intermediate IDU is not supported for Frame
Relay services. Besides connections across the satellite network 

Sky

WAN

®

 IDUs support also

local switching, i.e. PVCs connecting two serial ports on the same IDU.

In addition to unicast connections also multicast connections are possible. For a multicast PVC
a remote multicast group must be defined instead of remote IDU address and port number. Up
to 32 multicast groups are supported in a 

Sky

WAN

®

 network.  Stations which should receive

multicast data over the satellite interface and forward these data over one of their serial inter-
faces need a multicast group filter definition on at least one of their serial interfaces. This defi-
nition specifies which multicast group data flows should be forwarded over a specific serial port.

The 

Sky

WAN

®

 IDU supports Local Management Interface (LMI) procedures, which provide

regular status reports about the configured PVCs to attached Access Devices. The following
LMI standards are supported:

-

ANSI T1.617a Annex D 

-

ITU-T Q.933 Annex A

-

LMI Vendor Forum

A proprietary Node Status Message protocol allows the IDUs to exchange status information
about the status of activated serial ports and configured multicast group filter definitions on
these ports.

Содержание SKYWAN IDU 7000

Страница 1: ......

Страница 2: ......

Страница 3: ...ngineering Guide SkyWAN Indoor Unit IDU 7000 Software Rel 7 11 IDU 2570 Software Rel 7 11 IDU 2070 Software Rel 7 11 Document Number OM2044E_9400711 Document Revision B Revision Date 2010 10 26 IDU 10...

Страница 4: ...D SatCom Product GmbH hereafter referred to as ND SatCom which reserves all rights This document or parts of it may not be reproduced duplicated or distributed to third parties Nor may their content b...

Страница 5: ...2 Action objective after finish ing action steps Action Items are used to direct the user to execute the steps in the giv en order for a successful completion of the action fulfilled precondition for...

Страница 6: ...Page intentionally left blank 2 Network Design and Engineering Guide 2010 10 26...

Страница 7: ...Networking Overview 20 Voice connections 21 Voice Codecs 22 2 3 Essential SkyWAN Satellite Link Layer Features 23 2 3 1 SkyWAN Network Topologies 23 Reception Modes 24 2 3 2 Master and Slave Function...

Страница 8: ...l Data Input 57 2 6 1 1 Parameter Summary 58 2 6 2 Section Data Input per Frequency Channel 59 2 6 2 1 Parameter Summary 60 2 6 3 Area General Data Output 62 2 6 3 1 Parameter Summary 62 2 6 4 Area Da...

Страница 9: ...ta 88 Specify Network Data 88 Output Back Off 89 Stations with 2 Demodulator Boards 90 3 5 4 Tx Amplifier Worksheet 91 3 5 5 Summary Worksheet 92 Input 92 Output 93 Optional Link Filter for Complex To...

Страница 10: ...4 2 9 Robust Header Compression 122 4 2 10 Transmission Control Protocol Acceleration TCP A 123 4 3 SkyWAN Frame Relay Networking Features 125 4 3 1 Serial port properties 125 4 3 2 Basic Frame Relay...

Страница 11: ...between Modulation Coding and Carrier PEB 79 Table 3 4 Output Back Off SSPA 90 Table 3 5 Scenarion 1 2 Carrier Solution Requirements 101 Table 3 6 Scenario 1 Carrier Coding and Bandwidth 102 Table 3 7...

Страница 12: ...Page intentionally left blank 8 Network Design and Engineering Guide 2010 10 26...

Страница 13: ...lot Assignment with Ranging Subframe 34 Figure 2 18 Slot Assignment Differences 35 Figure 2 19 TDMA Structure of Throughput Example 36 Figure 2 20 Throughput Scenario 1 37 Figure 2 21 Throughput Scena...

Страница 14: ...ons 83 Figure 3 10 Uplink Considerations 84 Figure 3 11 Link Budget Tool Satellite Data Worksheet s 86 Figure 3 12 Link Budget Tool Antenna Data Worksheet s 87 Figure 3 13 Link Budget Tool C Band Ante...

Страница 15: ...col Stack IDU 7000 series 109 Figure 4 2 SkyWAN IP Protocol Stack IDU 1070 110 Figure 4 3 SkyWAN Meshed IP Data and Management Network 111 Figure 4 4 SkyWAN Hybrid IP Data and Management Network 112 F...

Страница 16: ...Page intentionally left blank 12 Network Design and Engineering Guide 2010 10 26...

Страница 17: ...neered for customer premisses Figure 1 1 Overview VSAT Station 1 2 Manual Content This SkyWAN Network Design and Engineering Guide provides information about how to de sign and engineer a SkyWAN Satel...

Страница 18: ...es A detailed description of the SkyWAN support of Data Networking Protocols TCP IP and Frame Relay will be given Implication for typical applications and services will be dis cussed Information for i...

Страница 19: ...n via Frame Relay and or IP GSM backhaul solutions SNMP based network management system L Band transmit and receive interface between indoor unit IDU and outdoor unit ODU SkyWAN Technology offers the...

Страница 20: ...ions a new design phase is required Customer Input which is required as a starting point for the design typically consists of the fol lowing information Description of applications and utilisation sce...

Страница 21: ...effi cient setup of configuration to install and commission a SkyWAN IDU station SkyWAN IDU 7000 1070 Series Station Com missioning Manual Describes how to assemble in stall and commission a Sky WAN...

Страница 22: ...Page intentionally left blank 18 Network Design and Engineering Guide 2010 10 26...

Страница 23: ...help of the ND SatCom TDMA Calculator tool Consider the resulting effects of the design approach to network efficiency network behavior and future expansions The original plain requirements refer to s...

Страница 24: ...ethernet port interface 1 SkyWAN supports the Internet Protocol IP routing functionality On the serial ports 2 5 interfaces 2 5 the Frame Relay FR switch ing functionality is supported a Both types o...

Страница 25: ...of the used voice codec typically in the range 6 64 kbps and the additional overhead due to the applied network protocol In SkyWAN networks two different network technologies are used Voice over IP u...

Страница 26: ...e 2 1 IP Voice Call Data Rates Table 2 2 Frame Relay Voice Call Data Rates Codec Codec Bit Rate bps Voice Payload byte Bit Rate Ethernet bps IP Bit Rate w o RoHC bps IP Bit Rate incl SLL encaps bps Ro...

Страница 27: ...brid topologies In a hy brid topology a part of the network may be fully meshed while some stations may only have star connectivity Or a multi star topology may be configured where the star terminals...

Страница 28: ...sented in the figure would need an RDR license whereas the star terminals could run with the default Limited Data Re ception LDR license The LDR license would still be sufficient if the star terminals...

Страница 29: ...enerator FPG board Satellite link requirement The master station must be able to reach each other station in the network over a satellite link with sufficient quality In a star or hybrid network this...

Страница 30: ...mended to configure two stations to be potential master stations Both sta tions have to fulfil the master station requirements mentioned before The station which enters the network first will become a...

Страница 31: ...rrier channel 1 The TDMA frame starts with a time slot furthermore notated as slot which is allocated to the active mas ter to transmit the reference burst The following slot is assigned to slave stat...

Страница 32: ...nfiguration and are referred to as Home Channel One and Home Channel Two SkyWAN stations can transmit data on any active carrier in the network frequency or carrier hopping By configuration the possib...

Страница 33: ...equest capacity on the home channel s of the receiving station if it is not already allocat ed Use the allocated time slot to transfer the data to the destination Data Slot Time Factors Base time slot...

Страница 34: ...eded for the request bursts 2 3 4 Downlink and Uplink Populations SkyWAN stations within a network can be grouped according to the carrier on which they re ceive the reference burst from the master an...

Страница 35: ...n carrier 1 only Symbolrate mod ulation and coding may be set differently on each carrier A graphical representation of the frame structure has been given in the section MF TDMA Functionality refer to...

Страница 36: ...r 2 for ranging and request bursts If only one uplink population exists in the network carrier 2 will not be defined The following restrictions apply Only one master station is possible no backup mast...

Страница 37: ...ovides transmit queues With these queues data to be send via satellite is treated differently regarding priority measures 1 Highest priority Real Time RT user data 2 Less priority Control data interna...

Страница 38: ...ned for this purpose If there are no unregistered stations in the network ranging slots can be allocated as dynamic data slots The size of the ranging section depends on the timeslot duration typicall...

Страница 39: ...on This makes sense if one wants to avoid the situation that high priority real time traffic is occupying 100 of the available slots on a carrier thus disrupting non real time application for an indef...

Страница 40: ...g slots from the common pool if its private pool is already exhausted Oversubscription with guaranteed throughput definitions is not allowed That means that for every carrier the sum of guaranteed slo...

Страница 41: ...yWAN FAD real time service should be ac tive between the stations Figure 2 20 Throughput Scenario 1 Effect Due to the defined guarantee for both stations the 6 dynamic slots needed for the PC applica...

Страница 42: ...used for the PC application 10 out of 12 available stream slots are already consumed by this application If there are in addition two parallel voice calls between IDU1 and IDU2 all available stream s...

Страница 43: ...cause the required 5 slots for each station are still available in the private pool If how ever an additional voice call is set up between the stations the additional streaming slot again must be take...

Страница 44: ...y additional streaming slot request from these stations would be rejected by the master even if there are still available slots in the common streaming pool Other stations could use this capacity for...

Страница 45: ...raffic IP or Frame Relay Voice traffic served by analog or digital SkyWAN FAD interfaces or VoIP systems For the purpose of traffic estimation it makes no difference if the traffic is based on the IP...

Страница 46: ...consisting of 50 stations Four different station groups station types are defined head offices big sites medium sites and small sites In figure 2 24 the non real time traffic flow between stations of...

Страница 47: ...mple account for only a small fraction of the network traffic they can be neglected in the estimation of the network traffic The next step is to summarize the traffic requirements to derive the user t...

Страница 48: ...lds in this spreadsheet are indicated by a grey background The following picture presents a work sheet filled with data from the example presented in this section Figure 2 26 Traffic Calculation Examp...

Страница 49: ...real time capacity for the type 4 stations not to individual stations but to the whole network as it is displayed in the following picture Figure 2 27 Per Network Traffic Erlang B Calculation Workshee...

Страница 50: ...ut header compression are already predefined in the sheet If an other codec should be used the data rate for a Custom Codec may be defined in the lookup table Note that the data rate must include the...

Страница 51: ...tations of a specific type The following picture represents that sheet filled with data from our network example Figure 2 29 Traffic Calculation Example Voice Traffic Flow Worksheet The input values i...

Страница 52: ...ative reasons the master stations must be located at the head offices There fore both stations of type 1 must be assigned to carrier 1 To create a 2 carrier solution with almost equally sized carriers...

Страница 53: ...y 256 kbps In that situation it may be more optimal to leave all small sites on one common carrier even if this leads to larger differences in data rates The last worksheet TDMA Calc Input is used to...

Страница 54: ...s If the hub station could not support the additional bandwidth due to power limitations one might be tempted to increase the network capacity by adding an additional carrier instead i e having a carr...

Страница 55: ...g a LAN packet over satellite 1 On reception of an Ethernet packet on the LAN port the SkyWAN IDU will first strip the Ethernet header The SkyWAN IDU operates as an IP router therefore Ethernet infor...

Страница 56: ...uirement for the carrier Figure 2 34 Add Turbo Phi Coding 4 The result of step 3 is a coded gross container which includes the error correction bits This information is transported over the satellite...

Страница 57: ...a brief period after a network restart once all stations are registered again at the active master these slots may be allocated as user traffic slots Figure 2 36 Signalling Time Slots 7 At this point...

Страница 58: ...For each step the additional overhead is specified explicitly Note the two different defini tions of data rates User data rate The data rate of user traffic received on the terrestrial interfaces LAN...

Страница 59: ...e exported and copied into the relevant configuration profile parameter A menu bar is available for exiting the application export and import to from a file and to show via and About entry the toolrel...

Страница 60: ...nd on the right the section Data Input per Frequency Channel Detailed descriptions for the particular fields are given in chapter 2 6 1 and chapter 2 6 2 For each channel input data can be specified s...

Страница 61: ...s selected to 2 a DUB mode is specified In this case additional input fields will appear refer to figure 2 40 The input field Size of UL population 1 defines the number of stations in the network Figu...

Страница 62: ...t 2 if a cross strapped satellite transponder is used Dual Uplink Mode DUB a second ULP has to be defined using carrier 2 Masterstation with self recep tion MRB and MRB DUB mode both require a master...

Страница 63: ...specified There are 6 different traffic types possible 1 FR Voice Frame Relay Voice Voice over SkyWAN FAD Select the appropiate Codec or protocol used 2 FR Realtime Frame Relay Real time 3 FR Non Rea...

Страница 64: ...ot sizes In combo box Time slot sizing ruled by choose 1 for slot size optimization depending on Frame Relay Voice traffic type 1 FR Voice If this option is selected the TDMA calculator defines the ba...

Страница 65: ...ype in the average packet size in byte of Real time Frame Relay traffic 2 FR Realtime of user data rate Type in the fraction of the user data traffic used for Frame Relay Real time traffic 3 FR Non Re...

Страница 66: ...ulting data rate per slot assignment will support the transport of one or multiple Frame Relay voice calls per slot Select 2 3 5 or 6 The base gross container size and slot time factor is defined in t...

Страница 67: ...length 1 optimized for the specified traffic Traffic is sent over satellite in coded gross container packages A base gross container holds the traffic data plus some overhead e g TDMA header SLL heade...

Страница 68: ...lculator For the definition of the user data refer to chapter 2 5 The spectral efficiency is represented by two definitions Efficiency per symbol user data rate symbol rate Efficiency per Hz user data...

Страница 69: ...ow many base slots are contained in one data slot for this channel Time slots per TDMA frame Displays how many time slots are contained in one TDMA frame for this channel Attention If the given number...

Страница 70: ...values manually Saved customer sheets can be imported in the TDMA Calculator using the Import function of the menu SkyNMS integrated TDMA Calculator after calculation click the button Apply to Configu...

Страница 71: ...lculation Tool The following results are important for the TDMA calculation The composition of the user traffic according to the different traffic types These numbers are used to define the correspond...

Страница 72: ...nt and Optimization Considerations 1 Evaluating the channel data output one notices that the number of time slots per TDMA frame larger than the maximum supported by SkyWAN networks Adjusting the time...

Страница 73: ...estimated by the Capacity Calculation presented at the beginning of this section All the assumptions made so far are still valid however we must now find a solution which provides sufficient user dat...

Страница 74: ...eded in the case of big time slots If this extra capacity cannot be used for additional traffic on this carrier it will be wasted 3 Since the same optimization criterion 2 voice calls per slot has bee...

Страница 75: ...hich will be explained in the following section of this guide Only after that calculation the proper value for Eb No can be inserted for each channel leading to a new selection of modulation and error...

Страница 76: ...Page intentionally left blank 72 Network Design and Engineering Guide 2010 10 26...

Страница 77: ...h stations The next steps in the engineering process are the choice of a suitable satellite rsp satellite transponder s and an optimized outdoor unit design 3 1 Introduction The general principle of t...

Страница 78: ...the area where the earth stations are located Typically two types of beams are available Wide beams global or hemispherical which cover a wide geographical area potentially including multiple contine...

Страница 79: ...a and Africa The NSS 7 global beam would cover the entire area If the stations would be located in Europe and Africa the east hemisphere beam would be more suitable because the beam intensity is typ i...

Страница 80: ...ection represents the signal propagation from the transmitting earth station to the satellite whereas the downlink part represents the signal path from the sat ellite to the receiving earth station Eq...

Страница 81: ...ture which is defined by the formula where kB is Boltzmann s constant and B the signal bandwidth The noise production by both the satellite and the earth station is usually combined with the antenna g...

Страница 82: ...s to use the highest possible value for modulation and FEC to save bandwidth costs without exceeding the maximum power available on both the satellite transponder and the earth stations Power Equivale...

Страница 83: ...PEB are identical Any further increase in modulation and coding will increase again the space segment cost as the PEB increases even though the carrier bandwidth would still decrease So the optimal m...

Страница 84: ...ain fade in the link budget calculation increases the power requirements on the earth stations and on the satellite transponder As an example we assume a situation where according to the required avai...

Страница 85: ...rain fade has disappeared refer to figure 3 7 Figure 3 7 Power Conditions with constant Power Level At clear sky condition the satellite transponder would operate at a power level which is 5 dB higher...

Страница 86: ...ut is always given by EIRPT EIRPT clear Sky Downlink rain fade Uplink rain fade 3 4 Considerations for SkyWAN Link Budget Calcu lations 3 4 1 Network Topology So far we have considered satellite links...

Страница 87: ...s used 3 4 2 Downlink Optimization Figure 3 9 Downlink Considerations The performance of the satellite downlink is given by the maximum available EIRP of the sat ellite the earth stations figure of me...

Страница 88: ...ownlink optimization discussion it was assumed that the satellite transmits with the max imum available EIRP to the earth stations This is however only true if the signal intensity re ceived from the...

Страница 89: ...for each network Result Power requirement for every SkyWAN earth station in the network The link budget tool is a Microsoft Excel spreadsheet which consists of the following work sheets Summary Input...

Страница 90: ...ow to specify signal degradation due to intermodulation on the up and downlink The default settings 300 200 dBW Hz describe a situation without intermodulation effects If no detailed information about...

Страница 91: ...angles 0 90 have to be inserted refer to figure 3 12 The antenna name for each data set has to be unique This name is used to link earth station properties to the antenna data In the case of C Band an...

Страница 92: ...splayed in the Active Calculation box blue background Specify Network Data Step 1 Specify each network by a Calculation Name Goto lower section Stored Calcu lations and enter network identifier headin...

Страница 93: ...ave a disadvantage of 0 dB for other sta tions the difference between maximum and actual G T or EIRP has to be entered Antenna type according to the defined frequency band of the network the pull down...

Страница 94: ...n additional back off has to be added which is defined on the summary work sheet refer to figure 3 18 If more than one IDU is connected to the same ODU besides an additional back off the power require...

Страница 95: ...specify the maximum power class available for SSPA amplifier types for Ku and C Band input field markde in figure 3 18 If the power requirement is higher than the available SSPA power class the additi...

Страница 96: ...bol rate have to be taken from the TDMA Calculator Additionally the following link quality parameters must be defined Maximum Bit Error Rate Two Way Rain Availability Step 2 For each carrier the netwo...

Страница 97: ...tion input box No input means that the power require ment for a station loop is calculated The last line states the required amplifier power including the station output back off Figure 3 20 Link Budg...

Страница 98: ...on with and without UPC are stated in terms of a power equivalent bandwidth and are compared to the carrier bandwidth of the station s home channel If the PEB with UPC is higher than the carrier bandw...

Страница 99: ...inks between stations located in these areas carriers on up to four different transponders may be required Carrier 1 must be located on a looped transponder for ULA1 This carrier is used by the master...

Страница 100: ...rope and Africa ULA1 and America ULA2 is presented The transponders used for this network are served by the hemispherical beams on the SES World Skies Satellite NSS 7 cf chapter 3 2 for foot print dia...

Страница 101: ...Network Hub Stations UpLink Area 1 ULA1 The slave stations of ULA1 use carrier 1 for the primary demodulator Any ULA1 station which should be able to communicate directly with a station in ULA2 must...

Страница 102: ...s mesh com munication within ULA2 Figure 3 28 MRB DUB Network ULA2 Stations Carrier Topology The definition of the carrier parameter topology in the summary sheet has to be done in the following way C...

Страница 103: ...A2 links to the master stations and to stations in ULA1 with a sec ond reception channel on carrier 2 will be calculated Additionally for slave stations in ULA2 with a second reception channel on carr...

Страница 104: ...os and typ ical optimization steps 3 6 1 Scenario 1 Ku Band 5 Stations Fully Meshed The first scenario is a fully meshed 5 station network located in a Ku Band spot beam over Eu rope and North Africa...

Страница 105: ...requirement of 8625 kbps Preliminary link calculation showed that a single carrier solution would lead to a very high power requirement for the earth stations Therefore it was decided to split the cap...

Страница 106: ...lting bandwidths Table 3 6 Scenario 1 Carrier Coding and Bandwidth The power requirements for the individual earth stations can be summarized in following table Table 3 7 Scenario 1 Summarized Power R...

Страница 107: ...station power requirement would be to split the network capacity into more than 2 carriers For small networks this may however cause inefficiencies if too few stations are sharing a carrier leading to...

Страница 108: ...hat there is really only negligible communica tion need between the remote stations Optimization There is still potential room for optimization Whereas on carrier 2 PEB and carrier bandwidth is almost...

Страница 109: ...ted for both carriers The bandwidth saving should again compensate the higher antenna and installation cost in Casablanca within a short time provided that the site in Casablanca allows the installati...

Страница 110: ...ilter matrix is used Network topology on carrier 2 is set to Meshed in ULA1 but the calculation of the satellite link loops for Casablanca and Tunis as well as the links between these two stations are...

Страница 111: ...one for user data one dedicated for man agement data The access to this interfaces is provided by 4 LAN ports refer to tables below 4 logical IP over Satellite interfaces for user traffic 1 IP over S...

Страница 112: ...face Sat UT1 SatOne is used data on this interface may be received by the primary or the secondary demodulator IP based management functions are e g uploading configuration files via FTP or querying s...

Страница 113: ...ure 4 1 SkyWAN IP Protocol Stack IDU 7000 series Table 4 1 IP Interface Usage of IDU 7000 series Interface Number Interface Name User or Management Plane 1 LAN User Management 8 Sat UT1 SatOne User Ma...

Страница 114: ...ter face Number Port Number Interface Name User or Management Plane 5 1 LAN1 User Traffic 5 2 LAN2 User Traffic 5 3 LAN2 User Traffic 5 4 LAN4 Management 9 Sat UT1 SatOne User Management 10 Sat UT2 Sa...

Страница 115: ...ed via its Sat MT interface to a common Manage ment IP network This management network is used to perform remote management of the en tire network via satellite using a SkyNMS PC which can be connecte...

Страница 116: ...to the same satellite management network like the meshed stations To ensure network management connectivity the station to which the SkyNMS PC is connected must have direct satellite link connectivity...

Страница 117: ...a star network may be enabled by defining static routes via the hub station Typical configuration is to define a default route on each star terminal with the hub station as a next hop and to define ex...

Страница 118: ...phic router identification is not supported Satellite interfaces may not belong to different OSPF areas The following OSPF features are available on SkyWAN stations Ethernet and satellite IP interface...

Страница 119: ...cal minimal path costs This mode works for both static routing and OSPF Non Equal Cost Multi Path Load balancing will be performed over all paths to a destina tion irrespective of the path cost This m...

Страница 120: ...s has a summary cost metric of 2 compared to a cost metric summary of 3 for the path R 2 via IDU 5 As long as IDU 4 and its Ethernet interface is up all IP unicast traffic will be routed via IDU 4 usi...

Страница 121: ...llocate sufficient capacity on all channels to perform the packet forwarding on eve ry channel IGMP Querier Role SkyWAN IDU supports the Internet Group Management Protocol IGMP version 2 This al lows...

Страница 122: ...SkyWAN IDU If enabled each IP microflow which should be forwarded to the satellite interface may be classified using protocol header information and rules defined in the station s for ward aggregate t...

Страница 123: ...d Silver Bronze and Default normal priority non real time traffic The high priority traffic is mapped to the IP Control 2 queue the normal priority traffic to the IP Non Real Time queue Capacity for t...

Страница 124: ...a maximum data rate for each Titanium aggregate Traffic ex ceeding this limit will be discarded Platinum Platinum forwarding aggregates define a permanent real time traffic flow When the aggregate is...

Страница 125: ...eways in our network multiple calls between these gateways would use IP flows with iden tical source and destination addresses Setting the flow detection parameter to flow would consider the streams g...

Страница 126: ...to compression will be released This capacity reduction works only for the audio codecs not for video codecs For data rate requirement for the above mentioned voice codecs with and without header com...

Страница 127: ...ed at each station 4 2 10 Transmission Control Protocol Acceleration TCP A The throughput of an individual TCP connection over long delay links is limited by the fact that the sender has to wait a lon...

Страница 128: ...ing system or applications are necessary The TCP acknowledgments will be sent by the local IDU with low delay thus the satellite delay has no impact on the TCP throughput Up to 32 TCP connections can...

Страница 129: ...the software license The following table 4 5 displays the possible port types Table 4 5 UIM Board FR Serial Port Types The interface standard is defined by the selected cable type Note that there are...

Страница 130: ...a direct single hop connection be tween the IDUs Double hop connectivity via an intermediate IDU is not supported for Frame Relay services Besides connections across the satellite network SkyWAN IDUs...

Страница 131: ...ed on the individual PVCs are forward ed to the satellite link The following figure 4 10 describes the mapping of communication serv ice to Frame Relay transmit queue on the IDU Figure 4 10 Mapping of...

Страница 132: ...he same PVC If a voice call setup is signaled by a FAD the SkyWAN IDU will automatically request suf ficient streaming slot bandwidth for the signaled voice codec If a call disconnect is signaled the...

Страница 133: ...rvice for Isochronous FRAD Ports An exception to these rules is the realtime service for isochronous FRAD ports Here the con figured serial port speed defines the required amount of streaming bandwidt...

Страница 134: ...Page intentionally left blank 130 Network Design and Engineering Guide 2010 10 26...

Страница 135: ...ration SkyWAN satellite link master and network parameters according to TDMA calcu lation result SkyWAN home channel settings SkyWAN satellite link station parameters according to used ODU hardware Tx...

Страница 136: ...y device Permanent virtual circuits PVCs have to be defined with a DLCI numbering scheme which may have to be adjusted to the customer s PVC topology The final result of the engineering process should...

Страница 137: ...bout new features in this release Table 6 1 What s new in the Engineering Manual Table 6 2 What s new in Rev B Number Item Description 1 TDMA calculation New TDMA Calculator introduced Number Item Des...

Страница 138: ...Page intentionally left blank 134 Network Design and Engineering Guide 2010 10 26...

Страница 139: ...t Error Rate Test CCR Convolutional Code Rate C N Signal to Noise Ration CRC Cyclic Redundancy Check CW Continuous Wave DC Direct Current DCE Data Communication Equipment DIAG Diagnostic DL Downlink D...

Страница 140: ...Frame Relay Access Devcice FRF Frame Relay Forum FTP File Transfer Protocol GSM Global System for Mobile communications GUI Graphical User Interface G T Gain to Noise Temperature HU Height Unit IBO In...

Страница 141: ...MIB Management Information Base MOD Modulator MRB Multiple Reference Burst MRB DUB Multiple Reference Burst Dual Uplink Beam NFB DUB No direct Feedback for Active Master Dual Uplink Beam NMS Network M...

Страница 142: ...eal Time Transport Protocol RTT Round Trip Time Rx Receive SAS Satellite Access Subsystem Sat MT Satellite Port Management Traffic Sat UT 1 4 Satellite Port User Traffic 1 to 4 synonym to SatOne SatTw...

Страница 143: ...er Control TOS Type of Service TTL Time to Live Tx Transmit TWTA Travelling Wave Tube Amplifier UDP User Datagram Protocol UFC Uplink Frequency Control UIM User Interface Module UL Uplink ULA Uplink A...

Страница 144: ...Page intentionally left blank 140 Network Design and Engineering Guide 2010 10 26...

Страница 145: ...using a fixed os cillator frequency Burst A short transmission over the satellite link The burst time is smaller than the time slot Carrier to Noise Ratio C N The ratio of the received carrier power a...

Страница 146: ...bit GEO Geostationary Earth Orbit satellites orbit at 35 786 km 22 282 mi above the equator in the same direction and speed as the earth rotates on its axis making them appear as fixed in the sky G T...

Страница 147: ...mbination of propagation queuing and processing delays is usually named network latency profile See also Propagation Delay and Processing Delay Low Noise Block Down Converter LNB Combination of Low No...

Страница 148: ...ons Cent er NOC Centralized location where control over operation of a network is managed and monitored remotely Network Management System NMS Hardware and software used for monitoring and controlling...

Страница 149: ...rainfall Reference Burst Burst sent from the SkyWAN master IDU containing TDMA network management information like the frame plan Request Burst Burst sent from the SkyWAN slave stations to the master...

Страница 150: ...by routing through a hub Symbol Rate Also known as baud or modulation rate is the number of sym bol changes signalling events made to the transmission me dium per second using a digitally modulated s...

Страница 151: ...igher 250 MByte of available hard disk space XGA 1024 x 768 or higher resolution video adapter and monitor CD ROM or DVD drive Keyboard and Microsoft Mouse or compatible pointing device Ethernet netwo...

Страница 152: ...on the installation CD A wizard will guide you through the installation process 4 If the correct Sun Java Runtime Environment JRE is not available on the PC hardware plat form it can be installed duri...

Страница 153: ......

Страница 154: ...www ndsatcom com...

Отзывы: