Misplaced Pages

Route filtering: Difference between revisions

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
Browse history interactively← Previous editNext edit →Content deleted Content addedVisualWikitext
Revision as of 12:41, 18 January 2008 editThe Anome (talk | contribs)Edit filter managers, Administrators253,417 edits Route filtering is generally carried out by ISPs for security reasons; for example, upstream ISPs generally only permit their transit customers to announce a limited range of IP address, to prevent ro← Previous edit Revision as of 12:42, 18 January 2008 edit undoThe Anome (talk | contribs)Edit filter managers, Administrators253,417 edits more...routesNext edit →
Line 1: Line 1:
{{context}} {{context}}


'''Route filtering''' is the concept, especially used on the global ] with ], of filtering (removing from your table) routes for certain prefixes (destination networks). Route filtering can apply both to routes learned from other routers, and routes announced to other routers. '''Route filtering''' is the concept, especially used on the global ] with ], of filtering (removing from your table) ]s for certain prefixes (destination networks). Route filtering can apply both to routes learned from other routers, and routes announced to other routers.


Route filtering is generally carried out by ISPs for security reasons; for example, upstream ISPs generally only permit their transit customers to announce a limited range of IP address, to prevent route hijacking attacks from within their customer networks. They are also likely to filter the routes they accept from other interconnected networks, to avoid their customers being the victims of route hijacking attacks from other networks. Route filtering is generally carried out by ISPs for security reasons; for example, upstream ISPs generally only permit each of their transit customers to announce a limited range of IP addresses, to prevent route hijacking attacks from within their customer networks. They are also likely to filter the routes they accept from other interconnected networks, to avoid their customers being the victims of route hijacking attacks from other networks.


Route filtering is also done because some routers have an insuffucient amount of ] in which to store the routing tables; as the global BGP table has grown, older routers (or any router running out of RAM) must filter routes in order to keep from running out of RAM (and crashing). This is usually done by removing of a route for any prefix more specific than a certain length (anything more specific than a /24, for example). Route filtering is also done because some routers have an insuffucient amount of ] in which to store the routing tables; as the global BGP table has grown, older routers (or any router running out of RAM) must filter routes in order to keep from running out of RAM (and crashing). This is usually done by removing of a route for any prefix more specific than a certain length (anything more specific than a /24, for example).

Revision as of 12:42, 18 January 2008

This article provides insufficient context for those unfamiliar with the subject. Please help improve the article by providing more context for the reader. (Learn how and when to remove this message)

Route filtering is the concept, especially used on the global Internet with BGP, of filtering (removing from your table) routes for certain prefixes (destination networks). Route filtering can apply both to routes learned from other routers, and routes announced to other routers.

Route filtering is generally carried out by ISPs for security reasons; for example, upstream ISPs generally only permit each of their transit customers to announce a limited range of IP addresses, to prevent route hijacking attacks from within their customer networks. They are also likely to filter the routes they accept from other interconnected networks, to avoid their customers being the victims of route hijacking attacks from other networks.

Route filtering is also done because some routers have an insuffucient amount of RAM in which to store the routing tables; as the global BGP table has grown, older routers (or any router running out of RAM) must filter routes in order to keep from running out of RAM (and crashing). This is usually done by removing of a route for any prefix more specific than a certain length (anything more specific than a /24, for example).

Stub icon

This Internet-related article is a stub. You can help Misplaced Pages by expanding it.

Category: