
Today I studied IS-IS Link-State Packet PDU's in more detail, specifically how it relates to both L1 and L2 links. I'm still a little confused on how pseudo-node works in broadcast networks but I have a feeling IS-IS is rarely if ever used as a routing protocol on a LAN network. It also got me to think about ES's (End-Systems) in a IS-IS Network. Since IS-IS uses an entirely different protocol than IP what host or computer even use IS-IS and CLNS instead of the IP stack? I'm going to have to do a little more digging around here but I suspect that it has something to do with the long history of IS-IS. I also went through my portable command book this evening and went through EIGRP commands and a simple lab using SSH instead of the usual console sessions. I think I'm going to go the security route so I might as well get used to encrypting passwords and locking down routers now! I hope everyone has Happy New Years, I won't be celebrating tonight due to my early shift tomorrow but I hope all my friends and family have fun and be safe tonight! 2010 is going to be a BIG year for me, I'm finally starting to see a shimmer of light at the end of the tunnel for a lot of goals I have set for myself.














![\bigg [ \bigg ( K_1 \cdot \text{Bandwidth} + \frac{K_2 \cdot \text{Bandwidth}}{256-\text{Load}} + K_3 \cdot \text{Delay} \bigg ) \cdot \frac {K_5}{K_4 + \text{Reliability}} \bigg ] \cdot 256](http://upload.wikimedia.org/math/c/8/b/c8bb6111fb31e61875ee63c17e797f7a.png)
