Tag Archives : bgp

In my last post I wrote some basics about the new 4-bytes AS number which is supported on new Cisco IOS images. Now I would like to give you a brief overview about different BGP peering scenarios that you can meet in the real world. Even if the configuration examples in this article are on a Cisco hardware...

Last week I received a form from APNIC with a new AS numbers. When I had a look through papers I saw there something strange: AS 123456 (I replaced the original with this number). 6 digits. First I thought that there is a mistake or something, then I recall the new 4-bytes ASN. If for IPv6 the things...

Official document on Cisco Security Advisory website Summary Cisco IOS XR Software contains multiple vulnerabilities in the Border Gateway Protocol (BGP) feature. These vulnerabilities include: Cisco IOS XR Software will reset a BGP peering session when receiving a specific invalid BGP update. The vulnerability...

Recent versions of Cisco IOS Software support RFC4893 (“BGP Support for Four-octet AS Number Space”) and contain two remote denial of service (DoS) vulnerabilities when handling specific Border Gateway Protocol (BGP) updates. These vulnerabilities affect only devices running Cisco IOS...

As we all know, in today’s digital communication world, there is a very big possibility that your network is or was target for a malicious activity. BGP is one of the most targeted routing protocols when we are talking about network attacks.Why? This is quite simple. BGP is your connection to the...

I was explaining in the previous post what is the difference between optimal and suboptimal path and how to avoid the use of not such a good path in your routed environment. Also there I presented this so call “dirty trick” you can use to force the routing protocol to choose the path that...

Everywhere in the world people try to find the optimal path to achieve something.If we speak about roads, trips and in our case networking, choosing the best path to an end point can have only advantages. I took the term optimal / suboptimal path from the routing issues that can appear in the OSPF network...

In some previous post we saw how we can manipulate BGP paths using attributes for outgoing traffic. Today we will see how to use another BGP attribute, but this time for manipulating inbound traffic. First I would like to ask you to have a look into the topology file and also to check the config files...