ND SatCom SKYWAN IDU 7000, Manual

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2010-10-26 Network Design and Engineering Guide 107
Data Networking
Introduction
4 DATA NETWORKING
A brief description of the data networking protocols supported on the Sky WAN
®
IDU was given
in chapter 2.2. This introduction was necessary to understand the user data rate requirements
needed as an input for the user traffic estimation.
4.1 Introduction
In this chapter details of the Sky WAN
®
implementation of the Internet Protocol (IP) as well as
the Frame Relay (FR) protocol will be presented.
4.2 SkyWAN
®
Internet Protocol Features
Since the intention of this guide is not to provide an introduction into IP networking, it is as-
sumed that the reader is familiar with the basics of IP networks and routing.
4.2.1 SkyWAN
®
IP Router Introduction
In the context of IP networking, each Sky WAN
®
IDU can be considered as a router with both
terrestrial and satellite IP interfaces. The following interfaces ( quantities in brackets) are avail-
able:
- Ethernet interfaces:
-
Sky WAN
®
IDU 7000 series: (1) Ethernet interface for management and user data;
- Sky WAN
®
IDU 1070: (2) Ethernet interfaces: 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 Satellite interface for management data;
- (1) service interface for local management access.
Interfaces may belong to the IP User or Management Plane, i.e. they are responsible for for-
warding user traffic or for access to the station management via IP based protocols.
The following table 4-1 and table 4-2 give an overview over all available IP interfaces on a Sky-
WAN
®
station. Note that the interfaces SatT-UT2 (SatTwo), Sat-UT3 (SatThree), Sat-UT4
(SatFour) are optional, in simple network topologies they are not needed. For security reasons,
access to management via the ethernet port can be restricted to specified hosts only.
Packet forwarding is performed by the IP network layer using static or dynamic IP routing pro-
cedures which will be discussed in the next sections. Data link layer functionality is provided by
the standard Ethernet Media Access Control (MAC) protocol, the Point-to-Point (PPP) protocol
for the service port and a proprietary
Sky WAN
®
IP over Satellite MAC protocol which includes
an optimized Address Resolution Protocol (ARP) for the satellite interface.