BGP4+ MED with IBGP

[Interoperability Test Scenario]

Last Update: August 31, 2000

This scenario verifies interoperability when the target ROUTER is attached to the model network.

Subjects:

  The MULTI_EXIT_DISC attribute (MED) may be used on external (inter-AS)
  links to discriminate among multiple exit or entry points to the same
  neighboring AS. MED is only comparable between routes learned from 
  the same neighboring AS. If two ASs connect to each other in more than 
  one place, it is useful to be able to choose the optimal link to reach
  a particular prefix in or behind that AS.


Verification Points :
- The target ROUTER can deal with the received MED attribute.
- The target ROUTER can send the all route or some route with the MED attribute.
- The target ROUTER can exchange the MED attribute between the router within 
  same AS.

Physical Network Configuration:

                     HOST-3      HOST-4 
            /           |           |            / 
            /(Net-u) ---+--+-   -+--+---- (Net-t)/
            /              |     |               /
            /      (I/F3-u)|     |(I/F3-t)       /
            /             ROUTER-3               /
            /      (I/F3-w)|     |(I/F3-v)       / AS 2000
            ////////////// | /// | ///////////////
                           |     |     
             (Net-w)       |     |      (Net-v)
                      +----+     +----+     
        ///////////// | ///////////// | ////////////
        /     (I/F-1w)| (I/F-1x)      |(I/F-2v)    /
        /         ROUTER-1----------ROUTER-2       / 
        /     (I/F-1z)|       (I/F-2x)|(I/F-2y)    /
        /             |    (Net-x)    |            /
        / (Net-z)--+--+-             -+--+--(Net-y)/
        /          |                     |         / 
        /       HOST-1                HOST-2       / AS 1000

(Net-t) (Prefix 3ffe:501:481d:f007::/64)
(Net-u) (Prefix 3ffe:501:481d:f006::/64)
(Net-v) (Prefix 3ffe:501:481d:f005::/64)
(Net-w) (Prefix 3ffe:501:481d:f004::/64)
(Net-x) (Prefix 3ffe:501:481d:f003::/64)
(Net-y) (Prefix 3ffe:501:481d:f002::/64)
(Net-z) (Prefix 3ffe:501:481d:f001::/64)

"///" : AS boundary

Network Prefix Network media

Net-t 3ffe:501:481d:f007::/64 Ethernet 10BASE-T

Net-u 3ffe:501:481d:f006::/64 Ethernet 10BASE-T

Net-v 3ffe:501:481d:f005::/64 Ethernet 10BASE-T

Net-w 3ffe:501:481d:f004::/64 Ethernet 10BASE-T

Net-x 3ffe:501:481d:f003::/64 Ethernet 10BASE-T

Net-y 3ffe:501:481d:f002::/64 Ethernet 10BASE-T

Net-z 3ffe:501:481d:f001::/64 Ethernet 10BASE-T

Test Machine:

Machine Comments Initial status Configuration

HOST-3 Reference Machine Is attached to Net-u with power turned off. -

HOST-4 Reference Machine Is attached to Net-t with power turned off. -

ROUTER-3 Reference Machine Power is turned off.
I/F3-t is attached to Net-t while
I/F3-u is attached to Net-u and
I/F3-v is attached to Net-v and
I/F3-w is attached to Net-w. AS number is 2000.
EBGP peer is ROUTER-1 (I/F1-w) of AS 1000.
EBGP peer is ROUTER-2 (I/F1-v) of AS 1000.
Send RA to Net-t and Net-u.

ROUTER-1 Target Machine Power is turned off.
I/F1-w is attached to Net-w while
I/F1-x is attached to Net-x and
I/F1-z is attached to Net-z. AS number is 1000.
EBGP peer is ROUTER-3 (I/F3-w) of AS 2000.
IBGP peer is ROUTER-2 (I/F2-x) of AS 1000.
Send RA to Net-z.

ROUTER-2 Reference Machine Power is turned off.
I/F2-v is attached to Net-v while
I/F2-x is attached to Net-x and
I/F2-y is attached to Net-y. AS number is 2000.
EBGP peer is ROUTER-3 (I/F3-v) of AS 2000.
IBGP peer is ROUTER-1 (I/F1-x) of AS 1000.
Send RA to Net-y.

HOST-1 Reference Machine Is attached to Net-z with power turned off. -

HOST-2 Reference Machine Is attached to Net-y with power turned off. -

Applications:
Interoperability is checked using traceroute application program.

Interoperability check

No Action Criteria Comments

1 Boot ROUTER-1. - -

2 Boot ROUTER-2. - -

3 Boot ROUTER-3. - -

4 Boot HOST-1. - -

5 Boot HOST-2. - -

6 Boot HOST-3. - -

7 Boot HOST-4. - -

8 At HOST-1, run "traceroute" to HOST-3's Global address. *Complete traceroute.
*ROUTER-1 -> ROUTER-3 -> HOST-3

9 At HOST-1, run "traceroute" to HOST-4's Global address. *Complete traceroute.
*ROUTER-1 -> ROUTER-3 -> HOST-4

10 At HOST-3, run "traceroute" to HOST-1's Global address. *Complete traceroute.
*ROUTER-3 -> ROUTER-1 -> HOST-1

11 At HOST-3, run "traceroute" to HOST-2's Global address. *Complete traceroute.
*ROUTER-3 -> ROUTER-1 -> ROUTER-2 -> HOST-2

AS1000 controls incoming all route using "MED"

12 At ROUTER-3, set "MED = 10" for all routes advertising to ROUTER-1(I/F1-w).

13 At ROUTER-3, set "MED = 1" for all routes advertising to ROUTER-2(I/F2-v).

14 At HOST-1, run "traceroute" to HOST-3's Global address. *Complete traceroute.
*ROUTER-1 -> ROUTER-2 -> ROUTER-3 -> HOST-3

15 At HOST-1, run "traceroute" to HOST-4's Global address. *Complete traceroute.
*ROUTER-1 -> ROUTER-2 -> ROUTER-3 -> HOST-4

16 At ROUTER-3, set "MED = 1" for all routes advertising to ROUTER-1(I/F1-w).

17 At ROUTER-3, set "MED = 10" for all routes advertising to ROUTER-2(I/F2-v).

18 At HOST-1, run "traceroute" to HOST-3's Global address. *Complete traceroute.
*ROUTER-1 -> ROUTER-3 -> HOST-3

19 At HOST-1, run "traceroute" to HOST-4's Global address. *Complete traceroute.
*ROUTER-1 -> ROUTER-3 -> HOST-4

AS1000 controls incoming specified route using "MED"

20 At ROUTER-3, set "MED = 10" against Net-u routes advertising to ROUTER-1(I/F1-w).

21 At ROUTER-3, set "MED = 1" against Net-u routes advertising to ROUTER-2(I/F2-v).

22 At HOST-1, run "traceroute" to HOST-3's Global address. *Complete traceroute.
*ROUTER-1 -> ROUTER-2 -> ROUTER-3 -> HOST-3

23 At HOST-1, run "traceroute" to HOST-4's Global address. *Complete traceroute.
*ROUTER-1 -> ROUTER-3 -> HOST-4

24 At ROUTER-3, set "MED = 10" against Net-t routes advertising to ROUTER-1(I/F1-w).

25 At ROUTER-3, set "MED = 1" against Net-t routes advertising to ROUTER-2(I/F2-v).

26 At HOST-1, run "traceroute" to HOST-3's Global address. *Complete traceroute.
*ROUTER-1 -> ROUTER-2 -> ROUTER-3 -> HOST-3

27 At HOST-1, run "traceroute" to HOST-4's Global address. *Complete traceroute.
*ROUTER-1 -> ROUTER-2 -> ROUTER-3 -> HOST-4

AS1000 add "MED" for outgoing all route via AS2000

28 At ROUTER-1, set "MED = 10" for all routes advertising to ROUTER-3(I/F3-w).

29 At ROUTER-2, set "MED = 1" for all routes advertising to ROUTER-3(I/F3-v).

30 At HOST-3, run "traceroute" to HOST-1's Global address. *Complete traceroute.
*ROUTER-3 -> ROUTER-2 -> ROUTER-1 -> HOST-1

31 At HOST-3, run "traceroute" to HOST-2's Global address. *Complete traceroute.
*ROUTER-3 -> ROUTER-2 -> HOST-2

32 At ROUTER-1, set "MED = 1" for all routes advertising to ROUTER-3(I/F3-w).

33 At ROUTER-1, set "MED = 10" for all routes advertising to ROUTER-3(I/F3-v).

34 At HOST-3, run "traceroute" to HOST-1's Global address. *Complete traceroute.
*ROUTER-3 -> ROUTER-1 -> HOST-1

35 At HOST-3, run "traceroute" to HOST-2's Global address. *Complete traceroute.
*ROUTER-3 -> ROUTER-1 -> ROUTER-2 -> HOST-2

AS1000 add "MED" for outgoing specified route via AS2000

36 At ROUTER-1, set "MED = 10" against Net-z routes advertising to ROUTER-3(I/F3-w).

37 At ROUTER-2, set "MED = 1" against Net-z routes advertising to ROUTER-3(I/F3-v).

38 At HOST-3, run "traceroute" to HOST-1's Global address. *Complete traceroute.
*ROUTER-3 -> ROUTER-2 -> ROUTER-1 -> HOST-1

39 At HOST-3, run "traceroute" to HOST-2's Global address. *Complete traceroute.
*ROUTER-3 -> ROUTER-1 -> ROUTER-2 -> HOST-2

40 At ROUTER-1, set "MED = 10" against Net-y routes advertising to ROUTER-3(I/F3-w).

41 At ROUTER-2, set "MED = 1" against Net-y routes advertising to ROUTER-3(I/F3-v).

42 At HOST-3, run "traceroute" to HOST-1's Global address. *Complete traceroute.
*ROUTER-3 -> ROUTER-2 -> ROUTER-1 -> HOST-1

43 At HOST-3, run "traceroute" to HOST-2's Global address. *Complete traceroute.
*ROUTER-3 -> ROUTER-2 -> HOST-2

Mark"*"with no number means that we are going to judge that subject.

Network	Prefix	Network media
Net-t	3ffe:501:481d:f007::/64	Ethernet 10BASE-T
Net-u	3ffe:501:481d:f006::/64	Ethernet 10BASE-T
Net-v	3ffe:501:481d:f005::/64	Ethernet 10BASE-T
Net-w	3ffe:501:481d:f004::/64	Ethernet 10BASE-T
Net-x	3ffe:501:481d:f003::/64	Ethernet 10BASE-T
Net-y	3ffe:501:481d:f002::/64	Ethernet 10BASE-T
Net-z	3ffe:501:481d:f001::/64	Ethernet 10BASE-T

Machine	Comments	Initial status	Configuration
HOST-3	Reference Machine	Is attached to Net-u with power turned off.	-
HOST-4	Reference Machine	Is attached to Net-t with power turned off.	-
ROUTER-3	Reference Machine	Power is turned off. I/F3-t is attached to Net-t while I/F3-u is attached to Net-u and I/F3-v is attached to Net-v and I/F3-w is attached to Net-w.	AS number is 2000. EBGP peer is ROUTER-1 (I/F1-w) of AS 1000. EBGP peer is ROUTER-2 (I/F1-v) of AS 1000. Send RA to Net-t and Net-u.
ROUTER-1	Target Machine	Power is turned off. I/F1-w is attached to Net-w while I/F1-x is attached to Net-x and I/F1-z is attached to Net-z.	AS number is 1000. EBGP peer is ROUTER-3 (I/F3-w) of AS 2000. IBGP peer is ROUTER-2 (I/F2-x) of AS 1000. Send RA to Net-z.
ROUTER-2	Reference Machine	Power is turned off. I/F2-v is attached to Net-v while I/F2-x is attached to Net-x and I/F2-y is attached to Net-y.	AS number is 2000. EBGP peer is ROUTER-3 (I/F3-v) of AS 2000. IBGP peer is ROUTER-1 (I/F1-x) of AS 1000. Send RA to Net-y.
HOST-1	Reference Machine	Is attached to Net-z with power turned off.	-
HOST-2	Reference Machine	Is attached to Net-y with power turned off.	-

No	Action	Criteria	Comments
1	Boot ROUTER-1.	-	-
2	Boot ROUTER-2.	-	-
3	Boot ROUTER-3.	-	-
4	Boot HOST-1.	-	-
5	Boot HOST-2.	-	-
6	Boot HOST-3.	-	-
7	Boot HOST-4.	-	-
8	At HOST-1, run "traceroute" to HOST-3's Global address.	Complete traceroute. ROUTER-1 -> ROUTER-3 -> HOST-3
9	At HOST-1, run "traceroute" to HOST-4's Global address.	Complete traceroute. ROUTER-1 -> ROUTER-3 -> HOST-4
10	At HOST-3, run "traceroute" to HOST-1's Global address.	Complete traceroute. ROUTER-3 -> ROUTER-1 -> HOST-1
11	At HOST-3, run "traceroute" to HOST-2's Global address.	Complete traceroute. ROUTER-3 -> ROUTER-1 -> ROUTER-2 -> HOST-2
AS1000 controls incoming all route using "MED"
12	At ROUTER-3, set "MED = 10" for all routes advertising to ROUTER-1(I/F1-w).
13	At ROUTER-3, set "MED = 1" for all routes advertising to ROUTER-2(I/F2-v).
14	At HOST-1, run "traceroute" to HOST-3's Global address.	Complete traceroute. ROUTER-1 -> ROUTER-2 -> ROUTER-3 -> HOST-3
15	At HOST-1, run "traceroute" to HOST-4's Global address.	Complete traceroute. ROUTER-1 -> ROUTER-2 -> ROUTER-3 -> HOST-4
16	At ROUTER-3, set "MED = 1" for all routes advertising to ROUTER-1(I/F1-w).
17	At ROUTER-3, set "MED = 10" for all routes advertising to ROUTER-2(I/F2-v).
18	At HOST-1, run "traceroute" to HOST-3's Global address.	Complete traceroute. ROUTER-1 -> ROUTER-3 -> HOST-3
19	At HOST-1, run "traceroute" to HOST-4's Global address.	Complete traceroute. ROUTER-1 -> ROUTER-3 -> HOST-4
AS1000 controls incoming specified route using "MED"
20	At ROUTER-3, set "MED = 10" against Net-u routes advertising to ROUTER-1(I/F1-w).
21	At ROUTER-3, set "MED = 1" against Net-u routes advertising to ROUTER-2(I/F2-v).
22	At HOST-1, run "traceroute" to HOST-3's Global address.	Complete traceroute. ROUTER-1 -> ROUTER-2 -> ROUTER-3 -> HOST-3
23	At HOST-1, run "traceroute" to HOST-4's Global address.	Complete traceroute. ROUTER-1 -> ROUTER-3 -> HOST-4
24	At ROUTER-3, set "MED = 10" against Net-t routes advertising to ROUTER-1(I/F1-w).
25	At ROUTER-3, set "MED = 1" against Net-t routes advertising to ROUTER-2(I/F2-v).
26	At HOST-1, run "traceroute" to HOST-3's Global address.	Complete traceroute. ROUTER-1 -> ROUTER-2 -> ROUTER-3 -> HOST-3
27	At HOST-1, run "traceroute" to HOST-4's Global address.	Complete traceroute. ROUTER-1 -> ROUTER-2 -> ROUTER-3 -> HOST-4
AS1000 add "MED" for outgoing all route via AS2000
28	At ROUTER-1, set "MED = 10" for all routes advertising to ROUTER-3(I/F3-w).
29	At ROUTER-2, set "MED = 1" for all routes advertising to ROUTER-3(I/F3-v).
30	At HOST-3, run "traceroute" to HOST-1's Global address.	Complete traceroute. ROUTER-3 -> ROUTER-2 -> ROUTER-1 -> HOST-1
31	At HOST-3, run "traceroute" to HOST-2's Global address.	Complete traceroute. ROUTER-3 -> ROUTER-2 -> HOST-2
32	At ROUTER-1, set "MED = 1" for all routes advertising to ROUTER-3(I/F3-w).
33	At ROUTER-1, set "MED = 10" for all routes advertising to ROUTER-3(I/F3-v).
34	At HOST-3, run "traceroute" to HOST-1's Global address.	Complete traceroute. ROUTER-3 -> ROUTER-1 -> HOST-1
35	At HOST-3, run "traceroute" to HOST-2's Global address.	Complete traceroute. ROUTER-3 -> ROUTER-1 -> ROUTER-2 -> HOST-2
AS1000 add "MED" for outgoing specified route via AS2000
36	At ROUTER-1, set "MED = 10" against Net-z routes advertising to ROUTER-3(I/F3-w).
37	At ROUTER-2, set "MED = 1" against Net-z routes advertising to ROUTER-3(I/F3-v).
38	At HOST-3, run "traceroute" to HOST-1's Global address.	Complete traceroute. ROUTER-3 -> ROUTER-2 -> ROUTER-1 -> HOST-1
39	At HOST-3, run "traceroute" to HOST-2's Global address.	Complete traceroute. ROUTER-3 -> ROUTER-1 -> ROUTER-2 -> HOST-2
40	At ROUTER-1, set "MED = 10" against Net-y routes advertising to ROUTER-3(I/F3-w).
41	At ROUTER-2, set "MED = 1" against Net-y routes advertising to ROUTER-3(I/F3-v).
42	At HOST-3, run "traceroute" to HOST-1's Global address.	Complete traceroute. ROUTER-3 -> ROUTER-2 -> ROUTER-1 -> HOST-1
43	At HOST-3, run "traceroute" to HOST-2's Global address.	Complete traceroute. ROUTER-3 -> ROUTER-2 -> HOST-2