Archive for the ‘ISP’ Category
Spamhaus DROP list
The Spamhaus DROP list (Don’t Route or Peer) is still awaiting it’s BGP feed for network providers. So in the meantime, I’ve knocked up a little PHP script that downloads the DROP list from Spamhaus and spits out either a list of IPtables rules or a Cisco access control list.
View Source: http://www.potato-people.com/code/misctools/spamhausdrop.phps
Download: http://www.potato-people.com/code/misctools/spamhausdrop.tar.gz
Pet Hate: MTR
MTR, also known as Matt’s Trace Route, is an enahanced traceroute utility which after making the initial run continues to rerun the traceroute and calculate hop-specific packet loss and latencies.
Unfortunately, virtually everytime someone calls me and mentions “packet loss” and “MTR” in the same breath, it’s because they do not understand the output.
Further musings on measuring bandwidth
A few further thoughts on things that people forget to take into account when attempting to measure bandwidth:
- When measuring bandwidth, attempt to use a site or tool that is close to your ISP. If you’re in the UK and you try to test your connection using a site hosted in the US it’s never going to give you a decent idea of your speed. I recommend Speedtest.net, as it’s a single tool that can test to a multitude of different locations and will give you a much better idea of exactly how your line is performing.
- Remember to allow around 10% for overheads. An 8Mb ADSL line will top out at 7.2Mbps. This is due to overheads for the ADSL line itself: a certain amount of bandwidth is required to manage your packets that will not be visible on any web-based bandwidth test.
- Any download requires a certain amount of packets to be sent in the opposite direction. Usually these are acknowledgement packets to assure the server you are downloading from that everything is being received okay (or not, as the case may be). Again, that magic 10% figure is the one to watch out for. A 1Mbps download will roughly need a 100Kbps upload. If you are using up all your upload bandwidth, your download bandwidth will be poor.
Dealing with DMCA notices in the UK
As I work in a ISP, I (unfortunately) have to deal with the abuse mailbox. And unfortuantely, these means responding to DMCA notices from US companies. How do you deal with a copyright infringement happening on your network, but when the holder is in the US and trying to apply US law?
DISCLAIMER: I am not a solicitor.