What is the answer
Last Post: March 16, 2006:
1.Which of the following conditions will prevent seamless roaming?
A. No MAC filters on the Access Points.
B. WEP key mismatch between clients and Access Points.
C. Use of different vendor?¡é?€??s IEEE 802.11b compliant DSSS hardware.
D. Mismatched SSID between clients and Access Points.
E. Roaming between FHSS and DSSS systems.
2.Which of the following results should be included in an RF Site Survey Report for an
indoor wireless LAN?
A. Measurements for current sources of RF interference.
B. An analysis of the clients existing network infrastructure.
C. Screenshots of the site survey software at particular coverage points.
D. Analysis detailing how well the clients particular application works over wireless.
E. What type of antennas should be used for building-to-building bridge links.
F. A list of what layer 3 protocols should be used over the wireless LAN for maximum
For seamless roaming
You check if the service set identifiers are matched, MAC filter on both units, spread spectrum technology on both units, matched wep keys b/w client and AP, ROaming b/w FHSS and DSSS, SSID b/w client and AP.
THese are some of the points you should always remember.
Answer is : B, D, E
2) for indoor site survey:
Are the APs from the same vendor. Most vendors implement roaming in a proprietary manner. Often LAN side issues are blamed on Wi-Fi.
IEEE draft 802.11r (corrected, used to be .11s... my bad) is addressing WLAN roaming. One day, hopefully, there'll be a standards-based way to do fast roaming from one vendor's AP to another's.
Isn't 802.11s releated to mesh networks, Does this also include fast roaming with different vendors, I have not gone through the IEEE document on this 802.11s, Just asked a quick question.
Nice to hear that
Mind cramp... I fixed it.
For ist question, why cant C be the answer.
For 2nd question, why cant C, D, F be the answer.
The important part of the question is "Which of the following conditions WILL prevent... "
Is it possible that using a different vendor's AP's would prevent roaming? Sure, it is possible, but the question specifically wants answers that WILL prevent roaming.
You could give screenshots (C) to the client, but they don't want to see that. They don't care what software you used.
Typically, a site survey would not include D unless specifically requested by the client. By that point it isn't much of a site survey anymore, its more of a live test in real world conditions. Whether the client's app works over wireless should have been determined before the site survey began.
There are so many reasons why F is not the right answer. I guess the first thing that throws me about the answer is that it is talking about L3 protocols. I didn't know that there was any important stuff above L2! :) Kidding.
Ok. Here's my shot.
"You could give screenshots (C) to the client, but they don't want to see that. They don't care what software you used."
Page 540 discusses Throughput and states "Be sure to include screenshots of the actual numerical measurements that were recorded if not using a passive site survey tool that records them for you"
I think F should not be correct for this question as the report "should focus on the best coverage patterns available" + equipment and interference. "Site survey report should not be turned into a consulting report for implementation and SECURITY"
Hope I am not violating anything here by quoting stuff I read from the Study guide.
I got the same doubt reading page-540 which also states that application analysis should be included in site survey reporting.
So i feel the answer is A,C,D for the 2nd question. Correct me if iam wrong.