From: Shuyi Li (shuli@xxxxxxxxx)
Date: Tue Jul 23 2002 - 18:13:25 GMT-3
The BW is used to communicate the bandwidth value of an interface to the
higher-level protocols, and being also used among protocols advertisements.
In the OSPF, briefly speaking, it's not very dynamic or accurate. Since
it's using the BW concept, which may not be the current available resource,
At 12:01 PM 7/21/2002 -0400, Peter van Oene wrote:
>The OSPF metric is dimensionless. That is to say its value is not
>designed to relate to any physical property. Most implementations,
>including Cisco, will automatically derive a value based upon the
>configured bandwidth of a link. However, this is the absolute configured
>bandwidth of the link, not the current bandwidth available. In other
>words, OSPF does not use a real time, utilization based metric. Doing so
>would most likely yield a lot of SPF churn as traffic moved around and
>produce a reasonably unstable network.
>
>Pete
>
>
>At 11:20 AM 7/17/2002 -0700, Shuyi Li wrote:
>>Jason,
>>
>>Regarding the OSPF metric, I have a question for you that, the cost of
>>links is considered to be the current available BW, or just the total BW
>>even it's being occupied, say 50%. Please advise.
>>
>>thanks in advance.
>>/shuyi
>>
>>
>>At 05:22 PM 7/17/2002 +1000, Jason Sinclair wrote:
>>>Tom,
>>>
>>>In OSPF the metric is the cost. What I mean here is best clarified as
>>>follows:
>>>
>>>1. In RIP the metric as we know is hop count.
>>>2. EIGRP/IGRP use a composite metric based on things such as bandwidth,
>>>delay, etc
>>>3. In OSPF the metric is based on the cost of links. The lower the cost the
>>>more preferred the path
>>>
>>>Hope this makes sense.
>>>
>>>Regards,
>>>
>>>Jason Sinclair CCIE #9100
>>>Manager, Network Control Centre
>>>POWERTEL
>>>55 Clarence Street,
>>>SYDNEY NSW 2000
>>>AUSTRALIA
>>>office: + 61 2 8264 3820
>>>mobile: + 61 416 105 858
>>>email: sinclairj@powertel.com.au
>>>
>>>-----Original Message-----
>>>From: Tom Young [mailto:gitsyoung@yahoo.co.jp]
>>>Sent: Wednesday, 17 July 2002 16:35
>>>To: ccielab@groupstudy.com
>>>Subject: OSPF 's cost and metric
>>>
>>>Hi, group.
>>>
>>> The OSPF's "cost" and "metric" parameters made me
>>>confused. Who can clear it for me?
>>>
>>>
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