Subject: [lisp] Understanding DDT

From: Sander Steffann <[email-masked]>
Date: Tue, 22 Jan 2013 10:51:39 +0100

Hi,

I am trying to understand the DDT protocol and I built a DDT node implementation in Python. I am currently doing very simple tests. Currently I'm just sending back DELEGATION-HOLE replies for 37.77.63.0/24 (some of my own address space). When playing with this from a Cisco device I get the results I expect from the lisp-rig command:

   #lisp-rig 37.77.63.4 to 194.33.96.96
   Send Map-Request to DDT-node 194.33.96.96 ... node referral, rtt: 0 ms
    EID-prefix: [0] 37.77.56.0/21, ttl: 1440
    referrals: 83.247.10.218, 87.195.109.18, 2001:9E0:411:1::10, 2001:9E0:810:1::10

   Send Map-Request to DDT-node 83.247.10.218 ... node referral, rtt: 0 ms
    EID-prefix: [0] 37.77.63.0/24, ttl: 1440
    referrals: 94.142.242.210, 2A02:898:148::210

   Send Map-Request to DDT-node 94.142.242.210 ... delegation hole, rtt: 8 ms
    EID-prefix: [0] 37.77.63.0/24, ttl: 15

But lig fails:

   #lig 37.77.63.66             
   ***Did not receive*** mapping information for EID 37.77.63.66
   Displaying information already present in cache:
   36.0.0.0/7, uptime: 00:10:58, expires: 00:03:54, via map-reply, forward-native
    Encapsulating to proxy ETR

When I do the same for a delegation-hole on a Cisco device I get:

   #lisp-rig 37.77.62.4 to 194.33.96.96
   Send Map-Request to DDT-node 194.33.96.96 ... node referral, rtt: 0 ms
    EID-prefix: [0] 37.77.56.0/21, ttl: 1440
    referrals: 83.247.10.218, 87.195.109.18, 2001:9E0:411:1::10, 2001:9E0:810:1::10

   Send Map-Request to DDT-node 83.247.10.218 ... delegation hole, rtt: 0 ms
    EID-prefix: [0] 37.77.62.0/24, ttl: 15

And a reply from lig:

   #lig 37.77.62.66 to 195.50.116.18        
   Mapping information for EID 37.77.62.66 from 195.50.116.18 with RTT 52 msecs
   37.77.62.0/24, uptime: 00:00:00, expires: 00:14:52, via map-reply, forward-native
    Encapsulating to proxy ETR

I must be doing something wrong, but I can't find what it is... I attached a tiny pcap file with the encapsulated map-requests and the corresponding responses I sent out. I really would appreciate it if someone could help me out!

Thanks,
Sander

PS: my test implementation is attached to the DDT tree and running, so feel free to experiment with it!
PPS: Oh, and the code is available under a BSD license at https://github.com/steffann/pylisp of course :-)

---

From: "Amit Jain (amijain)" <[email-masked]>
Date: Tue, 22 Jan 2013 18:51:44 +0000

Hi Sander,

>From what you list below, lisp-rig works but not lig. In lig, there is a timeout and if the reply does not come in that time, it lists as what you see below. Can you enable lisp mapping debugs and see if you do get a reply at all (from the MR saying hole)? If you dont, then we have to debug on the mapping system.

thanks, Amit

From: Sander Steffann <[email-masked]<mailto:[email-masked]>>
Date: Tuesday, January 22, 2013 1:51 AM
To: "[email-masked]<mailto:[email-masked]> list list" <[email-masked]<mailto:[email-masked]>>
Subject: [lisp] Understanding DDT

Hi,

But lig fails:

   #lig 37.77.63.66

And a reply from lig:

Thanks,
Sander

_______________________________________________
lisp mailing list
[email-masked]<mailto:[email-masked]>
https://www.ietf.org/mailman/listinfo/lisp