[HECnet] Network topology according to MIM.

[Johnny Billquist]

On 2016-01-15 04:18, Robert Armstrong wrote:
> As Peter said, HECnet isn't really optimized for performance.

In a way that is true. It's not optimal, if we talk about getting data 
travelling the most optimal path. But tries to be very efficient at not 
using much computing resources. Different parameters for "optimized for 
performance", and all that...

It does do optimal pack routing between routing nodes within an area. 
And it do optimal routing of packets between areas. It is the border 
line between endnode and router, and the ingress and egress to areas 
where it is just plain stupid.

> There's a joke about a Great Dane playing flyball (if you know anything about dog sports, you'll understand) - the amazing thing is not so much that he does it well, but rather that he does it at all.
>
>    HECnet is a little like that.

That HECnet works is not really that much of a trick.

And I just realized I think I can see what 1.1023 has for cost of the 
link to area 59, and I suspect the cost is 10... Which would mean I'd 
really have to bump the cost of the IP link up a lot to move over to 
that one. :-) At least some other links out from 1.1023 have a cost of 10.

	Johnny

>
> Bob
>
> On Jan 14, 2016 19:11, Johnny Billquist <bqt at softjar.se> wrote:
>>
>> On 2016-01-15 04:05, Robert Armstrong wrote:
>>> What happens if you make the cost on the LEGATO link 2 instead of 1?
>>>
>>> The cost on my Multinet links are all set to 2. Since your current LEGATO cost is 1, the total cost of that path to area 59 is 3.  The exactly equals the cost on you UNA circuit.  In the case of a tie on cost, DECnet picks the router with the lowest numerical address, hence LEGATO wins.
>>>
>>> But if you up the IP-0-0 cost to 2, the total would become 4 and the UNA would win.
>>
>> Yes, that would be correct.
>>
>> I'm still trying to decide which link to prefer, though...
>>
>> The problem is partly that this probably depends on how area 59 looks
>> inside, and which link 1.1023 is using. Am I mostly talking to nodes
>> close to the next hop from Legato, then the current setup is maybe best.
>> If I mostly talk to nodes close to the next hop from 1.1023, then it
>> makes sense to change this...
>>
>> Johnny
>>
>>>
>>> Bob
>>>
>>> On Jan 14, 2016 18:52, Johnny Billquist <bqt at softjar.se> wrote:
>>>>
>>>> Just FYI. It is slightly interesting and informing:
>>>>
>>>> 15-JAN-16   03:44:30 Node: MIM   (1.13) "RSX system at Update, Sweden"
>>>>                      RSX-11M-Plus, Area Routing Node, DECnet V4.6
>>>> Area Circuit Hop/Cst   Next Node        Area Circuit Hop/Cst   Next Node
>>>>      2 IP-0-0     1/1    LEGATO( 2.1)
>>>>      3 IP-0-0     2/3    LEGATO( 2.1)
>>>>      7 UNA-0      2/7    SG1   (19.41)
>>>>      8 UNA-0      1/3    GORVAX( 8.400)
>>>> 12 UNA-0      2/13         ( 1.1023)
>>>> 14 UNA-0      1/3    SKHNGW(14.4)
>>>> 18 IP-0-0     2/3    LEGATO( 2.1)
>>>> 19 UNA-0      1/3    SG1   (19.41)
>>>> 22 UNA-0      2/23   HUB   (42.1022)
>>>> 23 UNA-0      2/13         ( 1.1023)
>>>> 33 IP-0-0     2/3    LEGATO( 2.1)
>>>> 39 IP-0-0     2/3    LEGATO( 2.1)
>>>> 42 UNA-0      1/3    HUB   (42.1022)
>>>> 44 UNA-0      1/3    A44RTR(44.1023)
>>>> 59 IP-0-0     2/3    LEGATO( 2.1)
>>>> 61 UNA-0      2/23   HUB   (42.1022)
>>>> 62 UNA-0      1/3    CTAKAH(62.637)
>>>>      - Total areas: 17-
>>>>
>>>> Notice the number of areas that MIM now decided should go over IP-0-0,
>>>> which is the link to LEGATO. Since I set the cost for that link to 1,
>>>> while ethernet is at 3, it is rather favored. Not sure it really makes
>>>> sense to route packets to area 59 that way, since going over ethernet, I
>>>> would have a direct ptp to area 59 through a Cisco router sitting right
>>>> next to MIM, but that then becomes a question of what the cost of the
>>>> link between 1.1023 and area 59 is set to.
>>>>
>>>> Johnny
>>>>
>>>> --
>>>> Johnny Billquist                  || "I'm on a bus
>>>>                                       ||  on a psychedelic trip
>>>> email: bqt at softjar.se             ||  Reading murder books
>>>> pdp is alive!                     ||  tryin' to stay hip" - B. Idol
>>>>
>>
>>
>> --
>> Johnny Billquist                  || "I'm on a bus
>>                                     ||  on a psychedelic trip
>> email: bqt at softjar.se             ||  Reading murder books
>> pdp is alive!                     ||  tryin' to stay hip" - B. Idol
>>


-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol