User's Manual

Technical Guide
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Introduction
ISPs transport large volumes of data. They often have to pay large amounts of money to
transport their data through hired links, or through other providers' networks. Similarly, they
can also charge money for transporting other ISPs' data through their network.
Where significant amounts of money are involved, there are typically complex negotiations
involved, and agreements made that are bound by all sorts of rules and restrictions and
guarantees.
Hence, ISPs need to be able to very precisely control which data gets sent and received on
which links.This is achieved by having very precise control over the way the routing tables in
their routers are built.
To that end, the BGP implementation in AlliedWare Plus includes a set of facilities for filtering
routes, and for altering the attributes that are associated with certain routes in BGP update
messages. The main purpose of this document is to give an overview of these features, and
touches on how to configure them. One of the central route manipulation facilities is the
route map.
Route maps can also be used for manipulating OSPF routes, so this document concludes by
describing the use of route maps for OSPF.
Use Route Maps and Other Filters to Filter and Alter
BGP and OSPF Routes