Technology & MSG

As part of my undergraduate work at RIT, I took a course called Internetworking. While the classroom portion went into the guts of physical media specifications and computer networking, the lab component was by far more fun. We learned how to configure Cisco routers and switches. We learned how to do packet captures. We learned [...]

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On the debate between packet switching and circuit switching:
Generally speaking, people who do not like to hassle with restaurant reservations prefer packet switching.
– Kurose & Ross, Computer Networking: A Top-Down Approach (5th Edition)

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If you employ bogon filtering on your firewalls or servers, make sure you check the IPv4 address space list from time to time.
Since February 2008 and as recently as March 2009, IANA has allocated 13 /8 blocks that were previously unallocated. Here’s the complete list of new allocations from 2008 onward.
2008-02 173/8
2008-02 174/8
2008-05 112/8
2008-05 113/8
2008-10 [...]

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ZDnet reported that a set of F5 Networks’ BIG-IP load balancers are handling the official World Cup website. Despite this, F5 shares (NASDAQ: FFIV) are down $10 from last month.
SBS is hosting the web site from their headquarters in Sydney. The setup is 3-4 Sun Fire V240 servers, load balanced by a BIG-IP. Sun is [...]

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When configuring a Cisco PIX in Transparent Mode to operate across VLANs, take caution when using Foundry’s Virtual Ethernet (VE) interfaces.
On firewalls from Cisco, Transparent Mode is a significant new feature of PIX 7.0, where the firewall can be configured to behave like a Layer 2 bridge. Previously PIX devices behaved like an ACL-enhanced Layer [...]

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FreeBSD is not Windows in that the system won’t try to renegotiate a DHCP lease after having reconnected a network link that had been disconnected. Users who frequently swap networks under Windows are intimately familar with the ipconfig /renew command. While this obviously won’t work under FreeBSD, there is an equivalent command to renew a [...]

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