Dan Penn wrote: > > Check out the outline on CCO. As far as I know SNA, IPX, and > Applecrap, > I mean I talk, are still there for CID.
And, sir, why do you call it Applecrap? ;-) Seriously, can you provide some technical reasons to disparage it? Perhaps it's still on Cisco tests because the philosophies behind AppleTalk had a big impact on modern desktop protocol design. Also, many universities and schools of all sorts still have large AppleTalk networks. You would be surprised at how many still use it. It's also still used at scientific and graphics arts companies. Many protocol designers admire the pioneering work that Apple did to make networks plug and play. There's a new IETF working group called the Zero Configuration Networking group that credits AppleTalk. See here for more info: http://www.zeroconf.org/ Note that IPv6 has serverless autonegotiation of network-layer addresses which behaves quite a bit like AppleTalk. (It probably won't catch on in many environments which have a DHCP server, but it may catch on in other environments). And how about Microsoft's automatic addressing. (Of course we normally only see that when DHCP has failed, but still Microsoft thought enough of the AppleTalk mechanism to steal it. ;-) And how about service location? TCP/IP barely even has service location, still to this day. Don't you think it's a little silly that we have to find resources with a search engine? There is hope with new protocols like the Service Location Protocol (SLP) and some of the new multicast protocols that let you find multicasting servers. Note that the SLP RFC credits AppleTalk. Maybe some "expert" told you that AppleTalk is "chatty." For one thing, any protocol that tries to automate service location, speed up routing protocol convergence, and quickly workaround connection disconnects is going to be a bit chatty. It's a tradeoff. AppleTalk is no more chatty than Windows Networking or IPX. And you want chatty, how about all those keepalives and hellos that Cisco routers send? Maybe that same "expert" told you to avoid AppleTalk because it broadcasts too much. That's a myth. It uses multicasts, for one thing, which means a decent NIC driver that doesn't do AppleTalk shouldn't bother the host. The descriptions you see about Chooser behavior are mostly nonsense. The Chooser doesn't send broadcasts. It sends broadcast requests which are forwarded (as unicasts) to each router in the zone. Those routers send a multicast onto their networks in the zone. With good network design, this is no problem. The Chooser doesn't send continually unless the user leaves it open with a zone and service highlighted, which is almost never the case. Then it does send rather often, but backs off after 45 seconds. The problem where it sent the broadcast request packets (which are really unicasts) very often, without backing off, was fixed in 1989. By then, it was too late. The criticism of its behavior (even though already based on misinformation) was entrenched in people's minds. Hey, I could go on and on, but I'll stop here, you'll be glad to see. ;-) ________________________ Priscilla Oppenheimer http://www.priscilla.com > > Dan > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On > Behalf Of > suaveguru > Sent: Monday, July 15, 2002 9:53 AM > To: [EMAIL PROTECTED] > Subject: CID Exam 3.0 [7:48839] > > hi anyone knows what I should emphasize for the CID > exam ? Should I drop SNA , appletalk? What should I > concentrate on > > > thanks > > suaveguru > > __________________________________________________ > Do You Yahoo!? > Yahoo! Autos - Get free new car price quotes > http://autos.yahoo.com > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=48848&t=48839 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
