3/26/2011

sla udp-jitter

important point if you have to do UDP-JITTER SLA:


Time synchronization, such as that provided by NTP, is required between the source and the target device in order to provide accurate one-way delay (latency) measurements. To configure NTP on the source and target devices, perform the tasks in the "Performing Basic System Management" chapter of the Cisco IOS Network Manageent Configuration Guide. Time synchronization is not required for the one-way jitter and packet loss measurements, however. If the time is not synchronized between the source and target devices, one-way jitter and packet loss data will be returned, but values of "0" will be returned for the one-way delay measurements provided by the UDP jitter operation.

You must configure NTP between the routers you are measuring the jitter (under question, confirming that with the INE guys right now)



R5#show ntp as
R5#show ntp associations

address ref clock st when poll reach delay offset disp
*~172.16.101.1 127.127.7.1 3 40 128 377 8.2 -0.82 6.5
* master (synced), # master (unsynced), + selected, - candidate, ~ configured
R5#show ntp stat
R5#show ntp status
Clock is synchronized, stratum 4, reference is 172.16.101.1
nominal freq is 250.0000 Hz, actual freq is 249.9997 Hz, precision is 2**18
reference time is C0297209.88DEA666 (03:20:41.534 UTC Fri Mar 1 2002)
clock offset is -0.8210 msec, root delay is 8.22 msec
root dispersion is 7.39 msec, peer dispersion is 6.53 msec
R5#


R5#show ip sla statistics 1

Round Trip Time (RTT) for Index 1
Latest RTT: 11 milliseconds
Latest operation start time: 03:19:21.163 UTC Fri Mar 1 2002
Latest operation return code: OK
RTT Values:
Number Of RTT: 100 RTT Min/Avg/Max: 3/11/39 milliseconds
Latency one-way time:
Number of Latency one-way Samples: 0
Source to Destination Latency one way Min/Avg/Max: 0/0/0 milliseconds
Destination to Source Latency one way Min/Avg/Max: 0/0/0 milliseconds
Jitter Time:
Number of SD Jitter Samples: 0
Number of DS Jitter Samples: 0
Source to Destination Jitter Min/Avg/Max: 0/0/0 milliseconds
Destination to Source Jitter Min/Avg/Max: 0/0/0 milliseconds
Packet Loss Values:
Loss Source to Destination: 0 Loss Destination to Source: 0
Out Of Sequence: 0 Tail Drop: 100
Packet Late Arrival: 0 Packet Skipped: 0
Voice Score Values:
Calculated Planning Impairment Factor (ICPIF): 0
Mean Opinion Score (MOS): 0
Number of successes: 1
Number of failures: 0
Operation time to live: Forever

3/13/2011

lab 7; area border router election

how to push one of the routers in the broadcast ospf segment to be elected as a ABR; it's simple, based on rfc 1587 the only thing you should do is to make more preferable RID (higher RID)

linkedin vs facebook

I am quite sure I am able to explain what I think about the social networking and things like facebook but have you think about what would be if networks like linkedin extend their capabilities so you can actually chat with your business network or people interested in the same things as you. So, why facebook ? :) What facebook can offer you if you are looking for pro connections and people with common interests.

- my 1 cent thought

NMC labs 1 - 25

Looks like the recommendation from the most of people I asked is to skip the very first labs and jump on 26-35 (the version 4),however, still the very first labs are great in terms of building strong knowledge on things like redistribution,route filtering and troubleshooting. I am about to finish lab 7 and jump to lab 26.

3/10/2011

to review

NMC lab5; task 14.4;ipv6 l2 multicast

3/09/2011

NMC lab 5 task 2.1, table 4

Wrong vlan mappings for sw2 to R1;