03 June 2011

Review of Ubuntu 11.04

So I've installed Ubuntu 11.04 and played with a bit so far. While its generally the same deal as the previous version. (a user friendly yet full scale operating system) I have to say I am disappointed in the new unity desktop environment.

I personally find the unity desktop to be less user friendly then Gnome (my choice) or XFCE. It reminds of Mac OS-X with all the rolly, moving icons and strange menu set-up's. Now maybe as a linux and BSD guy, I have a bias against mac, but I've always found Mac overly complex to use. Further, all this fancy animated desktop requires something...things like RAM and processor power and a decent GPU. That to me is taking away from the essential things about linux. The fact it can generally be run on computers with very low system resources. I guess it still can, one could boot into gnome or Xterm, if gnome is heavy, Xterm and install XFCE. But I see no reason for the new desktop, Gnome was very functional, easy to use and is still my, and many of my fellow's, choice of a desktop.

Aside from that, its good, solid OS, as ubuntu always tends to be. It has a few bugs, but that's expected with any new release. Indeed, most of them have already been fixed with updates.

So overall, I think its a good solid release. I dislike unity, but hey, others might love it as a desktop, and you still get gnome installed incase you hate it. So it's hard to loose.

30 May 2011

networking how to and info-intro to network tech: Switchs, hubs, and routers-whats the difference?

networking how to and info-intro to network tech: Switchs, hubs, and routers-whats the difference?

Switchs, hubs, and routers-whats the difference?

I've noticed a lot of people mistake or misuse the terminology between switches, hubs and routers. I believe the reason for this is because quite often, a small office/home office (SOHO) router will contain a switch or a hub as well.

Lets start off with hubs. Hubs are a device that allow you to connect multiple hosts on the same network segment/subnet. Hubs are a fairly dumb device. Dumb in that they do not keep track of what traffic is coming or going from each host. Their solution is to simply broadcast all incoming packets. Broadcast on a small network being sending the packet of i.e. sending this traffic to every host. Hubs also do no do any load balancing, they split available bandwidth amongst all ports/all connected hosts. So if you have a regular DSL line and sharing it with 16 people, you can expect the connection to work like molasses on a cold day. That said, they do make switching hubs. Later in this article I will describe switches.

A switch is somewhat like hub, in that it allows the interconnection of many hosts on a single network segment or subnet. A switch varies because unlike a hub, it keeps a table of what host is sending and receiving what traffic. For example, instead of sending the packets on all ports to, it will send them "host 16" connected to port 16 on This causes the switch to be faster then a hub, more secure then hub (because its not broadcasting) and save internal bandwidth. (again because its not broadcasting. It also preserves outbound bandwidth by seeing what computers are transmitting and giving them bandwidth allocation, which results is better bandwidth management.

Now the fun stuff...routers. Routers, in the pure sense, are devices that read the header of the packet for its destination address and using routing tables and other routers, forwards this packet to other routers until finally it arrives at the destination network/host or the packet outlives its time to live or is dropped as unroutable. Nearly everyone has a router, as they are found at the gateways between networks, the most common and familiar one being the gateway between your Internet Service Provider and your internal Local Area Network. (even if that internal network consists of one host/computer its still considered at network and requires routing for its interconnection)

Typical SOHO routers that are embedded with DSL modems will contain in them a Dynamic host control protocol server, and facilities for Network Address translation. (I'll cover these concepts in another post) Routers tend to use a protocol like ICMP to communicate with each other, advertise their routes. (which address space they can route a packet to and how they do it) and other things that I'll cover in a post dedicated to routing. Aside from your SOHO routers, there is a polar opposite, the core router which runs on fiber optic backbone and handles 100's of megabits per second. Cisco and Juniper are well know manufactures of these types of routers. I'll close by saying, if it was not for routers, all the way from SOHO routers to core routers, the internet would simply fail. As historic note, the first router was called an "interface message processor" was as large as fridge, based on the Honeywell 516 computer and came out in 1969. It was *the* device that enabled ARPANET to work, and thus gave birth to the internet and packet switched networks in general

29 May 2011

How to obtain an IPVv6 tunnel on debian and ubuntu and windows with minial effort.

he.nethttp://gogonet.gogo6.com/page/freenet6-servicesSo, you've probably heard about IPv6. If not, I suggest reading the article at Wikipedia as short primer. Wikipedias ipv6 page In short, IPv6 is the emerging standard for Internet protocol addresses. (currently we mostly use the 32 bit IPv4 address, the all so familiar "" as an example) However, the pool of IPv4 address's has run dry, and now what is coming out is the IPv6 address, which provides for 128bit addresses that look like "2001:0:53aa:64c:2c91:c387:ba5a:505f"  Expressed in hexadecimal and having many more unique address's to choose from.

Okay so you want to use IPv6 but your ISP does not offer it yet. Well don't let that stop you. There services called tunnel brokers, who will give you a "tunnel" over IPv4 to carry IPv6 packets. For both Debian and Ubuntu Linux, this is an easy task.

You can go to freenet6 if you have if you have Microsoft windows, follow the on screen instructions, download their client program, and volia! you have IPv6 connectivity. If you have Debian or Ubuntu Linux, obtain the package "gogoc" either though snypatic package manager, or by using the command line "sudo apt-get install gogos" That package will automatically make a tunnel between you and their IPv6 tunnels. Another tunnel broker is Hurricane Electric Their tunnels however, require more technical know how to configure, so if your just new to this, I suggest gogo6/freenet6. However, Hurricane offers you a routed /48 block of addresses, which if you know how to use, is quite the gift... Now to check your IPv6 connectivity try using IPv6 version of google. If the page loads, congratulations, you are now part of the IPv6 collection of interconnected networks, also termed an Internet!

If it does not load or there is no obvious manner to set up a 6in4udp tunnel, try searching the Internet for the specifics of configuring your operating system to allow IPv6 connectivity.  

I hope you found this post informative and useful.

New blog

So this is my new blog. I am a networking technician who has decided to write a blog about computer sciences, networking and howto's related to computers, as well as things related to linux and BSD.
Tomorrow, I plan to write a proper technical post. but this our first post.