RuggedCom RuggedRouter RX1100 - Manual (Page 91)

10. Multilink PPP over T1/E1
Revision 1.14.3 91 RX1000/RX1100™
10. Multilink PPP over T1/E1
10.1. Introduction
This chapter familiarizes the user with:
• Multilink PPP in overview
• Configuring Multilink PPP
• Viewing MLPPP statistics
10.1.1. Multilink PPP Fundamentals
The PPP Multilink Protocol (also known as Multilink PPP) is defined in Internet RFC 1990. Its purpose
is to combine two or more PPP links into one so-called "bundle" in order to provide more bandwidth
to a point to point connection.
PPP Multilink must be supported on both sides of the link, and may be used if there is more than one
PPP link connecting the two endpoints. It works by multiplexing data on a per-packet basis to transmit
across multiple PPP links. Sequence numbering is used to attempt to preserve the order of packets
transmitted across the bundle.
RuggedRouter is capable of running PPP Multilink over two or more T1/E1 links. It is capable of
defining only one MLPPP bundle.
10.1.2. Notes on T1/E1 Channelization
T1/E1 lines can be configured as "channelized" or "unchannelized". A more complete discussion
of this topic than the one provided below can be found in the section on
Strategy For Creating
Interfaces .
In unchannelized mode, an entire T1/E1 link is aggregated into one channel. In the MLPPP Channel
Setting table below, unchannelized T1/E1 interfaces will be seen to have only one channel: channel 1.
In channelized mode, more than one channel is defined for each T1/E1 interface. The section on
Strategy For Creating Interfaces describes the process of creating multiple channels on a T1/E1
interface. Note that in order for PPP Multilink to operate optimally, it is advisable to ensure that each
link in the MLPPP bundle has the same bandwidth. This means that the number of time slots, the
clocking mode and rate for each T1/E1 link that is used by PPP Multilink should be the same.
10.2. Configuring PPP Multilink over T1/E1
In order to begin creating an MLPPP bundle, click on T1/E1 in the Networking folder of the main
Webmin menu. T1/E1 Trunks and Interfaces will display the menu below: