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so many ip addresses so little time…

Tuesday, September 30, 2008

RFC1925 The Twelve Networking Truths

The Fundamental Truths

(1) It Has To Work.

(2) No matter how hard you push and no matter what the priority,
you can't increase the speed of light.

(2a) (corollary). No matter how hard you try, you can't make a
baby in much less than 9 months. Trying to speed this up
*might* make it slower, but it won't make it happen any
quicker.

(3) With sufficient thrust, pigs fly just fine. However, this is
not necessarily a good idea. It is hard to be sure where they
are going to land, and it could be dangerous sitting under them
as they fly overhead.

(4) Some things in life can never be fully appreciated nor
understood unless experienced firsthand. Some things in
networking can never be fully understood by someone who neither
builds commercial networking equipment nor runs an operational
network.

(5) It is always possible to aglutenate multiple separate problems
into a single complex interdependent solution. In most cases
this is a bad idea.

(6) It is easier to move a problem around (for example, by moving
the problem to a different part of the overall network
architecture) than it is to solve it.

(6a) (corollary). It is always possible to add another level of
indirection.

(7) It is always something

(7a) (corollary). Good, Fast, Cheap: Pick any two (you can't
have all three).

(8) It is more complicated than you think.

(9) For all resources, whatever it is, you need more.

(9a) (corollary) Every networking problem always takes longer to
solve than it seems like it should.

(10) One size never fits all.

(11) Every old idea will be proposed again with a different name and
a different presentation, regardless of whether it works.

(11a) (corollary). See rule 6a.

(12) In protocol design, perfection has been reached not when there
is nothing left to add, but when there is nothing left to take
away.

The Twelve Networking Truths RFC1925

posted by nullrouter at 8:51 pm  

Tuesday, September 30, 2008

It’s been quiet…

Knee deep in CCIE Lab preperation / Study…. Sorry guys :)

posted by nullrouter at 8:48 pm  

Friday, August 22, 2008

CCIE Wireless Beta Exam

Received an email today from Cisco, advertisting the start of Beta written exams for the CCIE Wireless path. It will be available from October, and the usual beta exam cost of $50 US. Usual VUE exam outlets.

(more…)

posted by nullrouter at 12:34 am  

Friday, August 8, 2008

Basic Multicast AutoRP and BSR setup v0.1

AutoRP

All Participating Multicast Routers
ip multicast-routing

either:

Router(config-if)#ip pim sparse-dense mode

OR

Router(config)#ip pim autorp listener
Router(config-if)#ip pim sparse mode

*AutoRP relies on dense mode for RP and Mapping Agent communication, therefore if sparse mode is configured on an interface, then ip pim autorp listener needs to be configured to enable dense mode flooding for 224.0.1.39 and 224.0.1.40

Candidate RP:
Router(config)#ip pim send-rp-announce (interface or ip address)
Router(config)#ip pim rp-announce filter rp-list (access-list unicast) group-list (access-list multicast)

RP Relay Agent:
Router(config)#ip pim send-rp-discovery (interface or ip address)

BSR (utilised PIM v2)
All Participating Multicast Routers, including RP and BSR routers
:
Router(config)#ip multicast-routing
Router(config-if)#ip pim sparse-mode

RP and BSR routers only:
Router(config)#ip pim bsr-candidate (interface)
Router(config)#ip pim rp-candidate (interface)

posted by nullrouter at 2:38 am  

Monday, July 28, 2008

Juniper: Juniper Networks Certification Fast Track Program

If you’re looking at an alternative to Cisco certifications, or looking at expanding your horizons like all good networkers should. You should check out the Juniper fast track program, and take up some of the discounted offers on Juniper Certifications for the Enterprise tracks, especially if you have exposure to Juniper equipment.

http://www.juniper.net/training/fasttrack/

I’ll be looking at boosting my own Juniper knowledge once I get this CCIE lab out of the way. There’s also no shortage of reference material out there on the net. Again something to look into if you are wanting to get an edge career wise.

posted by nullrouter at 2:04 am  

Saturday, July 26, 2008

Cisco News: Cisco Support Wiki launches

Cisco has launched their very own support wiki page found here. It’s full of how to’s and all things that should stop you from scratching your head when trying to remember how to configure a few things.

Clearly this will not be available during the CCIE Lab exams :p, so for us potentials we still need to get used to the DocCD setup… for now at least.

posted by nullrouter at 8:28 pm  

Saturday, July 26, 2008

Cisco News: Cisco and Pearson VUE Launch Global Test Delivery Exam Security Enhancements

Ok hopefully this is true with what’s to be implemented with the Computer Based exams. I don’t think many people out there are impressed, when someone posts their perfect exam score and the fact it only took them 5 minutes to complete a 50 question based exam.

Let’s also hope that questions on the exams are also more to the point regarding the technology and knowledge required for the certification, rather than vague, full of double negatives like some certification questions.

Cisco and Pearson VUE Launch Global Test Delivery Exam Security Enhancements

(more…)

posted by nullrouter at 8:13 pm  

Saturday, July 26, 2008

Cisco News: CCDE Lab Beta offering

Looks like you’ll need to be going to Chicago if you’re looking at doing this one.

(more…)

posted by nullrouter at 8:07 pm  

Saturday, July 26, 2008

Cisco News: CCNA Wireless Training available (#640-721 IUWNE)

Cisco has announced the training path for the CCNA Wireless certification:

(more…)

posted by nullrouter at 8:05 pm  

Saturday, July 26, 2008

IPv6 Special Prefixes

Some of us may have a few IPv6 references, however if they’ve been around for longer than say 2006, especially some books, then some of the specific ranges, and some ‘addressing layers’ have become obsolete, and you might not be aware. IPv6 is still in a state of flux with addresses formatting.

Specific IPv6 current address ranges of note that are still current:

Link Local Range

  • ::/128 - An unspecified address for software use only.
  • ::1/128 - localhost loopback address (IPv4 equivalent 127.0.0.1).
  • fe80::/10 - link local addresses to be used between hosts on the same link, IPv6 services, and routing protocols will be making use of this, instead of 224.0.0.0/24 with a TTL of 1). Also will replace the IPv4 LinkLocal/ZeroConf range of 169.0.0.0

Site Local Range

  • fc00::/7 - Unique Local addressing, not routable in the global address space. Used for private IPv6 and VPNs

Multicast Range

  • ff00::/8 - Range for Multicast traffic.

IPv4 Usage/Tunneling Transport Range

  • ::ffff:0:0/96 - used to map IPv4 addresses within the IPv6 routing table
  • 2001:0000::/32 - used for Host to Host/Teredo Tunneling, encapsulating IPv6 packets within IPv4 UDP datagrams. Usefull for when traversing infrastructure where IPv6 support may not exist.
  • 2002::/16 - Used for 6 to 4 tunneling methods, usually each IPv6 network will be attached with atleast one IPv4 network.

Documentation Range

  • 2001:db8::/32 - This range is was reserved specifically for the use within documentation examples.

Deprecated/Abandoned Ranges

  • ::/96 - zero prefix used for IPv4 compatibility
  • fec0::/10 - Site local prefixed intended to replace private address ranges in IPv4, has been replaced with fc00::/7 Unique Local Address range

Implementing IPv6 Addressing and Basic Connectivity

posted by nullrouter at 6:11 pm  
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