Re: DDOS Attack Mitigation

From: Darren Reed (avalonat_private)
Date: Tue Feb 15 2000 - 17:50:27 PST

  • Next message: Elias Levy: "Re: "Association of Responsible Internet Providers"?"

    In some mail from Hugh LaMaster, sie said:
    [...]
    > > > The simplest ingress filtering to stop IP address
    > > > spoofing on a Cisco is simply to apply the following
    > > > to stub network interfaces:
    > > >
    > > >  ip verify unicast reverse-path
    > > >
    > > > I assume that this is mostly what people are talking about
    > > > in this context.
    > >
    > > How recent is this in terms of IOS releases ?
    >
    > Well, it was/is in 11.1(17)CC and later CC images, which
    > goes back about 2 or 2-1/2 years or so, and, it has been
    > in all 12.0(x)S.  I'm not sure about all other 12.0 images,
    > since we have used 11.1(x)CC and 12.0(x)S images since I've been
    > here - but, the web pages imply that it is in most/all 12.0 images;
    > the -CC and -S trains are the so-called ISP versions,
    > which transit ISPs use, and, which many campuses and Tier 2-4
    > providers should probably also use on their borders and aggregation
    > routers.
    
    Hmm,from a 1720:
    
    gw#show version
    21:07:33: %SYS-5-CONFIG_I: Configured from console by console
    Cisco Internetwork Operating System Software
    IOS (tm) C1700 Software (C1700-Y-M), Version 12.0(3)T3,  RELEASE SOFTWARE (fc1)
    Copyright (c) 1986-1999 by cisco Systems, Inc.
    Compiled Thu 15-Apr-99 13:58 by kpma
    Image text-base: 0x80008088, data-base: 0x804FC75C
    
    ROM: System Bootstrap, Version 12.0(1)XA1, RELEASE SOFTWARE (fc1)
    
    ...
    gw(config)#ip verify unicast reverse-path
                       ^
    % Invalid input detected at '^' marker.
    
    Darren
    



    This archive was generated by hypermail 2b30 : Fri Apr 13 2001 - 15:35:31 PDT