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IPv6 Essentials
Carla Schroder writes "IPv6 is halfway here, so network administrators need to learn their way around it whether they want to or not. Adoption has been slower in the United States because we possess the lion's share of IPv4 addresses, but even so, someday IPv4 is going away for good. And, there is more to it than just increasing the pool of available addresses. IPv6 has enough improvements over IPv4 to make it worth the change even if we weren't running out of IPV4 addresses, such as built-in IPSec, simplified routing and administration, and scalability that IPv4 simply can't support. We're moving into gigabyte and multi-gigabyte backbones, and high-demand real-time services like voice-over-IP and streaming audio and video that require sophisticated QoS (quality of service) and bandwidth prioritization. IPv6 can handle these, IPv4 can't." Read on for the rest of Carla's review.
IPv6 Essentials, 2nd Edition
author
Silvia Hagen
pages
436
publisher
O'Reilly Media, Inc.
rating
10
reviewer
Carla Schroder
ISBN
0-596-10058-2
summary
practical, in-depth guide to implementing and administering IPv6
IPv6 Essentials, 2nd edition, by Silvia Hagen, released in May 2006, is a well-written, clear, up-to-date guide to understanding IPv6 in-depth. This is a real accomplishment, because computer networking protocols are completely abstract, and translating all of these abstractions into understandable language is a noteworthy feat. The book explains how it all works to a very practical depth, so that the reader will be well-prepared to begin implementation.
What it does not cover is the specifics of configuring network devices, such as routers, switches, and interface cards, and this is not a flaw, because those things are platform- and vendor-dependent. Having a solid understanding of the protocol itself is more important, and something that is sadly lacking even in today's IPv4 world. The Internet would be a better place if more network admins would take the time to learn IP fundamentals.
Ms. Hagen does a nice job of covering the following topics: Strengths and advantages, such as auto-configuration, and good-bye to NAT, The structure of the protocol itself, including header format, Improved security, Real genuine QoS, Simplified routing, Co-existence with IPv4, Painless mobile networking, and Addressing. Addressing is one of the scariest parts. When you're used to slinging around something like 192.168.1.100 with ease, coming eye-to-eye with something like this, 3ffe:ffff:1001:0000:2300:6eff:fe04:d9ff, is a bit disconcerting.
But fear not, for Ms. Hagen dissects IPv6 addresses clearly and in detail, showing that they have a logical, consistent, understandable structure. For example, the first quad (3ffe) tells you that this is a 6bone.net address, so it is already obsolete because the 6bone closed down in June 2006. Other prefixes tell you if it is a private address, link-local, site-local, and so on. The book lays this all out in tables, and explains what each one is for.
How would you like to retire your DHCP servers permanently? No problem. IPv6 auto-configures hosts all by itself, or you may exercise as much control as you like. Ms. Hagen explains the various options- link-local, site-local, stateful, stateless, neighbor discovery, and so forth, and what you can do with them. For example, with IPv6 you can whip up an ad-hoc LAN with hardly any effort, and without needing special servers or client software.
Security is built-in to IPv6, instead of bolted-on as it is for IPv4. However, IPSec (IP Security) is still largely untested and unproven on a number of levels, so the book discusses both the pros and cons.
The book covers the problems, hassles, and compromises that come with using NAT (network address translation). We're used to it now, but sometime down the road we're going to look back and think "Wow, that was one big fat pain. Good thing it's gone."
The chapter on Mobile IPv6 is almost worth the price of the book by itself. IPv6 supports both wired and wireless mobile users in an elegant, hassle-free way. Say good-bye to setting up multiple profiles, or hassling with scripts. Roaming users can keep the same IP as they travel — across different networks, wired to wireless- anywhere they go. This little bit of magic occurs because IPv6 assigns them multiple IPs. One is the home address, which is permanent. A second address is the care-of address, which changes as the user moves around. Of course there is a lot more to it that just having multiple addresses, and like everything else in this book, Ms. Hagen explains how it works clearly and understandably.
The book is abundantly illustrated in the usual quality O'Reilly fashion, and the illustrations are invaluable for understanding the material.
We're at the stage where IPv6 support is pretty much universal- you can count on both network hardware and software supporting it. So the network administrator only needs to focus on learning the ins and outs of implementation. I recommend IPv6 Essentials as an essential reference, and a great starting point for mastering IPv6.
You can purchase IPv6 Essentials, 2nd Edition from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
IPv6 Essentials, 2nd edition, by Silvia Hagen, released in May 2006, is a well-written, clear, up-to-date guide to understanding IPv6 in-depth. This is a real accomplishment, because computer networking protocols are completely abstract, and translating all of these abstractions into understandable language is a noteworthy feat. The book explains how it all works to a very practical depth, so that the reader will be well-prepared to begin implementation.
What it does not cover is the specifics of configuring network devices, such as routers, switches, and interface cards, and this is not a flaw, because those things are platform- and vendor-dependent. Having a solid understanding of the protocol itself is more important, and something that is sadly lacking even in today's IPv4 world. The Internet would be a better place if more network admins would take the time to learn IP fundamentals.
Ms. Hagen does a nice job of covering the following topics: Strengths and advantages, such as auto-configuration, and good-bye to NAT, The structure of the protocol itself, including header format, Improved security, Real genuine QoS, Simplified routing, Co-existence with IPv4, Painless mobile networking, and Addressing. Addressing is one of the scariest parts. When you're used to slinging around something like 192.168.1.100 with ease, coming eye-to-eye with something like this, 3ffe:ffff:1001:0000:2300:6eff:fe04:d9ff, is a bit disconcerting.
But fear not, for Ms. Hagen dissects IPv6 addresses clearly and in detail, showing that they have a logical, consistent, understandable structure. For example, the first quad (3ffe) tells you that this is a 6bone.net address, so it is already obsolete because the 6bone closed down in June 2006. Other prefixes tell you if it is a private address, link-local, site-local, and so on. The book lays this all out in tables, and explains what each one is for.
How would you like to retire your DHCP servers permanently? No problem. IPv6 auto-configures hosts all by itself, or you may exercise as much control as you like. Ms. Hagen explains the various options- link-local, site-local, stateful, stateless, neighbor discovery, and so forth, and what you can do with them. For example, with IPv6 you can whip up an ad-hoc LAN with hardly any effort, and without needing special servers or client software.
Security is built-in to IPv6, instead of bolted-on as it is for IPv4. However, IPSec (IP Security) is still largely untested and unproven on a number of levels, so the book discusses both the pros and cons.
The book covers the problems, hassles, and compromises that come with using NAT (network address translation). We're used to it now, but sometime down the road we're going to look back and think "Wow, that was one big fat pain. Good thing it's gone."
The chapter on Mobile IPv6 is almost worth the price of the book by itself. IPv6 supports both wired and wireless mobile users in an elegant, hassle-free way. Say good-bye to setting up multiple profiles, or hassling with scripts. Roaming users can keep the same IP as they travel — across different networks, wired to wireless- anywhere they go. This little bit of magic occurs because IPv6 assigns them multiple IPs. One is the home address, which is permanent. A second address is the care-of address, which changes as the user moves around. Of course there is a lot more to it that just having multiple addresses, and like everything else in this book, Ms. Hagen explains how it works clearly and understandably.
The book is abundantly illustrated in the usual quality O'Reilly fashion, and the illustrations are invaluable for understanding the material.
We're at the stage where IPv6 support is pretty much universal- you can count on both network hardware and software supporting it. So the network administrator only needs to focus on learning the ins and outs of implementation. I recommend IPv6 Essentials as an essential reference, and a great starting point for mastering IPv6.
You can purchase IPv6 Essentials, 2nd Edition from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
So, does that mean we're using IPv5 now?
Author of Enyo: Up and Running from O'Reilly Media
Back in the day, the 8080 architecture had 16-bit addresses, which limited you to 64 KB of memory. The 8086 used segement registers to allow 16-bit registers to address up to 1 MB of memory. But data structures were still limited to 64 KB unless you were willing to slow down your access time by a factor of four or more, and sharing data between code running in different segments required even more jumping through hoops. NAT allows more devices than IPv4 can address to communicate with central servers that aren't running NAT, but setting up P2P between systems that are both using NAT is damn near impossible.
Good-bye, IPv4, and good riddance.
Nothing for 6-digit uids?
The summary cites QoS as a motivating feature to adopt IPv6, and this is not a good thing. The very nature of the Internet (as an end to end best effort network) makes it impossible to guarantee any sort of service. As such, the only usage of prioritization is unfairly biasing some network resources at the expense of others. This is a direct affront on network neutrality.
The only place packet prioritization and traffic shaping should take place is on private networks, where QoS can be guaranteed. Services such as VOIP and IPTV would ideally be offered over these ISP local networks at an additional cost. This is not to say that VOIP over the Internet impossible, but it should not have an unfair advantage over other Internet traffic.
The only place where things break down is in the last mile, where ISPs are selling bandwidth that does not exist. In this case, something has to give, and so they must implement unfair prioritization schemes. The obvious solution is to honestly advertise minimum guaranteed rates instead. This makes it possible to prioritize a customers own traffic as the customer wishes without affecting others. (For example, if you want VOIP prioritized to the ISP local VOIP network.)
Of course, such a scheme would still allow different speed grades, and excess capacity to be utilized. It can not be emphasized enough though that prioritization has no place on the Internet itself.
You are describing an inherant flaw in Vonage/Sunrocket/Etc. style VoIP services.
As a cable company, their traffic looks no different then Jo Shmoe next door torrenting the latest Back Door Betty DVD. So we CAN'T apply QOS to that traffic. We don't throttle it down OR up. We just let it go, and rely on the subscriber to know how to set up QOS on their equipment to maximize problems caused by their INTERNAL network.
However, VoIP services such as those offered by Time Warner, Comcast, and actual ISPs CAN be prioritized because the MTA in the customer's home gets it's own IP address, and we know all traffic from that block of addresses is VoIP, and thus gets priority!
Full Disclosure: Time Warner Cable Tier 3 Technician here.
Until we have something that everyone wants and ONLY works with IPv6, we're not going to switch. That "thing" might be here today, but it seems we're all unaware what it is.
Sure, there may be things that are better, but I can do all of the things IPv6 can do with IPv4 and a slew of extra services that I'm already familar with (VLAN or service-based QoS, NAT, DNS, DHCP, etc).
I for one REALLY want IPv6 to get here, but the people who make my software and pay for my equipment won't change until they need to.
Grammer Nazis - I mod you "troll" unless you actually add something on-topic. Yes, I know I have mispellings in my sig.
What will happen first?
Example: 192.168.1.2.3
Or is the goal to try and push IPv6 simply because it's "better?"
As I understand it one of the main reasons IPV4 wasn't just extended in address space was because routing becomes too difficult with such a large address space, so you need to build routing into the protocol. There's also some very cool features of IPV6 like multi-casting that's been very poorly supported under IPV4. This would allow things like broadcasting internet based TV without multi-gigabyte connections.
When the day comes that said ISP calls me up to tell me "Hey, we're changing over to IPv6 at the end of the month (or year, or whatever), so you need to be ready for it," THEN I will start worrying about how to implement it.
That'll probbably never happen (or at least not for 20 years maybe). IPV4 isn't going away, what'll happen (someday) is your ISP will one day support IPV6 and you'll be able to get an IPV6 IP address. No one is going to call you up, you'll probbably have to call them up and ask if they're supporting it.
Until then, V4 and NAT are working perfectly well for me, thanks.
Well, I'm sure horse and buggy owners thought that horses were perfectly good transportation when the car first came out too. There weren't many paved roads, the things were expensive, and took special fuel to run them where horses just ran on oats. It's often hard to see the advantages of a new technology before it's hit the mainstream.
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