Go CCIE Go!! - A Cisco Certified Internetwork Expert

Which forum are you sending the message to? I have not seen your message at all…
Knowing which lab would help too, but let’s try generic answers…
1. EUI-64 forces the router to assign the host portion of the IPv6 address based on the MAC address (or based on the link-local ipv6 address defined). It’s merely a shortcut to providing all 128 bits of address to the router and save yourself some typing (partcularly when it comes to MAC addresses!) Whether you use it or not is completely your own decision unless the lab specifically tells you otherwise.
2. If you just use one, will you have full reachability? Try “debug ipv6 packet” and do some pings. Try some pings THROUGH the interface as well once routing is working.
3. Summarization in IPv6 works EXACTLY like it does n IPv4. At least at a binary level. It’s just bigger and uglier.
So to summarize, we break it in binary as you did. And with those numbers/binary, you appear to be correct that it should be a /59. If I knew what lab we were talking about I could really better answer it or figure out if there were different requirements in addition to those two numbers!
HTH,
Scott Morris, CCIE4 #4713, JNCIE-M #153, JNCIS-ER, CISSP, et al. CCSI/JNCI-M/JNCI-ER Senior CCIE Instructor
smorris@internetworkexpert.com

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—–Original Message—– From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of Nitro Drops Sent: Tuesday, August 19, 2008 3:20 AM To: ccielab@groupstudy.com Subject: IEWB - IPv6 Queries
Hi Folks,
Need some kind advices from network experts, have tried the IE forum, but no replies.
Q1. Task 6.1 : IPv6 “eui-64″ When configuring IPv6 addresses on the interfaces, when do i need to include IPv6 host address “eui-64″? 2001:192:10:X::/64 eui-64 In R1, “eui-64″ is used on the F0/0 interface. But not on R2’s F0/0 and R5’s E0/1. Is “eui-64″ needed only when I need to carry out a static frame-relay map statement? Q2. Task 6.2 : Frame-Relay map statement on R2 Instead of using 2 x Frame-Relay map statements, one for the IPv6 /64 Network and one for the Link Local /64Host, can i just use 1 x Frame-Relay map statement for an /128 IPv6 Network + Host instead frame-relay map ipv6 FE80::204:27FF:FEB5:2F60 201 frame-relay map ipv6 2001:141:1:12::1 201 broadcast into frame-relay map ipv6 2001:141:1:12:204:27FF:FEB5:2F60 201 broadcast Q3. Task 6.3 : Summarize IPv6 address Is the summarized mask supposed to be /59 instead of /58? 2 characters = 1 byte = 8 bits 2001:141:1:12 = 2001 (16bits) : 0141 (16bits) : 0001 (16bits) : 0012 (00000000 0000 1100) 2001:141:1:25 = 2001 (16bits) : 0141 (16bits) : 0001 (16bits) : 0025 (00000000 0001 1001) Summarised Masks = 16 + 16 + 16 + 11 = 59 bits? (From Left to Right) Thanks for any kind replies. Much appreciated.
Cheers Nit
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