Community IN BGP...
What does this mean : "IF A ROUTER DOESNOT UNDERSTAND THE CONCEPT OF COMMUNITIES IT WILL DEFER TO THE NEXT ROUTER" Please help. Thanks Manish _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Community IN BGP...
Here's a guess. The BGP community attribute is optional, yet transitive. This means that a particular implementation of BGP on a router may not use or understand the concept of communities. However, because the attribute is transitive, it will be forwarded along to other neighbors who may be able to to use it. I'm sure someone will correct me if I have the wrong. Regards, John > What does this mean : > > "IF A ROUTER DOESNOT UNDERSTAND THE CONCEPT OF COMMUNITIES IT WILL DEFER TO THE NEXT ROUTER" > > Please help. > Thanks > Manish > > _ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] ___ Send a cool gift with your E-Card http://www.bluemountain.com/giftcenter/ _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Community IN BGP...
I could understand this since this is a transitive attribute and therefore it can transit the routers and can be passed. But there is a condition imposed by whereby it says that the remote router maynot understand the community but it shall be configured to propogate it to the next hop destination or transit router else by default the communities are dropped. Now if the communities are dropped "does this mean that the route is dropped" since the coomunity attribute is resposible for the routes ... Thanks Manish John Neiberger wrote: > Here's a guess. The BGP community attribute is optional, yet transitive. > This means that a particular implementation of BGP on a router may not use > or understand the concept of communities. However, because the attribute is > transitive, it will be forwarded along to other neighbors who may be able to > to use it. > > I'm sure someone will correct me if I have the wrong. > > Regards, > John > > > What does this mean : > > > > "IF A ROUTER DOESNOT UNDERSTAND THE CONCEPT OF COMMUNITIES IT WILL DEFER > TO THE NEXT ROUTER" > > > > Please help. > > Thanks > > Manish > > > > _ > > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > > ___ > Send a cool gift with your E-Card > http://www.bluemountain.com/giftcenter/ > > _ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Community IN BGP...
If a given router does not understand or use the community attribute, the route is not dropped and the community is passed along in updates sent to other BGP neighbors. The statement you originally posted simply says this: Any given router need not use the community attribute, but that information must remain intact so that other routers might make use of it should they decide to do so. A BGP community is strictly an administrative attribute. It has zero effect on routing if your router is not configured to use that information. However, your router needs to forward that information intact to other neighbors in case they need it to enforce whatever routing or filtering policies they have implemented. HTH, John > I could understand this since this is a transitive attribute and therefore it can > transit the routers and can be passed. > But there is a condition imposed by whereby it says that the remote router maynot > understand the community but it shall be configured to propogate it to the next hop > destination or transit router else by default the communities are dropped. Now if the > communities are dropped "does this mean that the route is dropped" since the coomunity > attribute is resposible for the routes ... > > Thanks > Manish > > John Neiberger wrote: > > > Here's a guess. The BGP community attribute is optional, yet transitive. > > This means that a particular implementation of BGP on a router may not use > > or understand the concept of communities. However, because the attribute is > > transitive, it will be forwarded along to other neighbors who may be able to > > to use it. > > > > I'm sure someone will correct me if I have the wrong. > > > > Regards, > > John > > > > > What does this mean : > > > > > > "IF A ROUTER DOESNOT UNDERSTAND THE CONCEPT OF COMMUNITIES IT WILL DEFER > > TO THE NEXT ROUTER" > > > > > > Please help. > > > Thanks > > > Manish > > > > > > _ > > > FAQ, list archives, and subscription info: > > http://www.groupstudy.com/list/cisco.html > > > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > > > > ___ > > Send a cool gift with your E-Card > > http://www.bluemountain.com/giftcenter/ > > > > _ > > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > ___ Send a cool gift with your E-Card http://www.bluemountain.com/giftcenter/ _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Community IN BGP...
Thanks John, I got it. Thanks Manish John Neiberger wrote: > If a given router does not understand or use the community attribute, the > route is not dropped and the community is passed along in updates sent to > other BGP neighbors. The statement you originally posted simply says this: > Any given router need not use the community attribute, but that information > must remain intact so that other routers might make use of it should they > decide to do so. > > A BGP community is strictly an administrative attribute. It has zero effect > on routing if your router is not configured to use that information. > However, your router needs to forward that information intact to other > neighbors in case they need it to enforce whatever routing or filtering > policies they have implemented. > > HTH, > John > > > I could understand this since this is a transitive attribute and > therefore it can > > transit the routers and can be passed. > > But there is a condition imposed by whereby it says that the remote > router maynot > > understand the community but it shall be configured to propogate it to > the next hop > > destination or transit router else by default the communities are > dropped. Now if the > > communities are dropped "does this mean that the route is dropped" since > the coomunity > > attribute is resposible for the routes ... > > > > Thanks > > Manish > > > > John Neiberger wrote: > > > > > Here's a guess. The BGP community attribute is optional, yet > transitive. > > > This means that a particular implementation of BGP on a router may not > use > > > or understand the concept of communities. However, because the > attribute is > > > transitive, it will be forwarded along to other neighbors who may be > able to > > > to use it. > > > > > > I'm sure someone will correct me if I have the wrong. > > > > > > Regards, > > > John > > > > > > > What does this mean : > > > > > > > > "IF A ROUTER DOESNOT UNDERSTAND THE CONCEPT OF COMMUNITIES IT WILL > DEFER > > > TO THE NEXT ROUTER" > > > > > > > > Please help. > > > > Thanks > > > > Manish > > > > > > > > _ > > > > FAQ, list archives, and subscription info: > > > http://www.groupstudy.com/list/cisco.html > > > > Report misconduct and Nondisclosure violations to > [EMAIL PROTECTED] > > > > > > ___ > > > Send a cool gift with your E-Card > > > http://www.bluemountain.com/giftcenter/ > > > > > > _ > > > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > > > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > > > > ___ > Send a cool gift with your E-Card > http://www.bluemountain.com/giftcenter/ _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
