ITS wrote:The IT Service Desk opened the following call for you on 16/11/2005 at
09:09:27:
Your port has been blocked due to a suspected breach of acceptable use
policy.
Please Contact Gill Buxton on ext. 23254 to arrange an appointment with
Mary Visser, deputy director of IT, as soon as possible.
ITS Blocking Ports
Moderator: Operators
well i rang up this morning and had my meeting ect i will post further details later when my internet gets re-connected but i got this email after i rang up ITS =)
How eactly do ITS/ResNet know who are using DC++? Is it just by port and address of people connecting to the hub or do they actually look in the packets for DC++ traffic?
I was thinking about this and then wondering exactly what they are allowed to look at in your traffic. It doesn't say they reserve the right to, or say the opposite in their AUP. Infact the AUP is pretty useless in most respects as it doesn't even say what they mean by 'Peer to Peer file sharing applications'. Unfortunately it does specifically mention DC++ although I'd personally argue that as a hub based system it isnt strictly peer to peer. If it is, then surely MSN Messenger or even windows itself with it's file sharing is exactly the same?
I was thinking about this and then wondering exactly what they are allowed to look at in your traffic. It doesn't say they reserve the right to, or say the opposite in their AUP. Infact the AUP is pretty useless in most respects as it doesn't even say what they mean by 'Peer to Peer file sharing applications'. Unfortunately it does specifically mention DC++ although I'd personally argue that as a hub based system it isnt strictly peer to peer. If it is, then surely MSN Messenger or even windows itself with it's file sharing is exactly the same?
Not completely sure bout it. but I they definetly monitor ports and I believe with most P2P apps they also monitor the packets looking for the specific protocol, but DC++ uses a protocol very similar to http and so this would be hard in the case of DC++.oliford wrote:How eactly do ITS/ResNet know who are using DC++? Is it just by port and address of people connecting to the hub or do they actually look in the packets for DC++ traffic?
Well I believe that "Peer to Peer" is enough description.. It means all the applications using P2P protocols. But otherwise generally I do agree that the AUP is not very informative and very vague.oliford wrote:Infact the AUP is pretty useless in most respects as it doesn't even say what they mean by 'Peer to Peer file sharing applications'.
No as I mentioned above P2P applications use P2P protocols and their connections are made in similar ways with "Direct Connection" (DC="Direct Connect"). Even though DC++ uses a hub most of the actual traffic does not go through the hub (except with passive users), thus most traffic is "Direct". MSN on the other hand has nothing to do with P2P and uses a slightly different protocol. It also can make several connections, but often its bandwidth usage is far smaller..oliford wrote:Unfortunately it does specifically mention DC++ although I'd personally argue that as a hub based system it isnt strictly peer to peer. If it is, then surely MSN Messenger or even windows itself with it's file sharing is exactly the same?
Another point which has been made several times on this forum is that there are differences between P2P apps in the way they use bandwidth. ie Bittorrent is a whore and will often take far too much and can indeed be damaging to a network, especially the larger it gets.
I'm not entirely sure about the ITS strategy as it seems a bit confusing. ppl have already pointed out that if they can monitor individual ports (which I believe they can) then why are they using this new system of reduced bandwidth for subnets?? Hopefully maybe the focus group meeting will allow for some answers. Hopefully the ITS staff present will be competent enough to actually answer tecnical questions. It would be typical to simply put a speaker with little actual technical knowledge on the stand as he can simply say "I'm sorry I dont quite kno. I will have to check up on that!"
When you chat to someone on MSN, don't the chat messages (and file transfers) go directly to the person you are chatting to? I know this is how ICQ at least used to work (when it's not the case that both parties are firewalled). If so, MSN is P2P in the same way DC is P2P - you connect to a central server to get userlists and talk directly to other peers.echelon wrote:MSN on the other hand has nothing to do with P2P and uses a slightly different protocol. It also can make several connections, but often its bandwidth usage is far smaller..
Cocodude
it does if both users have ticked the "allow msn to connect directly" box in the options.When you chat to someone on MSN, don't the chat messages (and file transfers) go directly to the person you are chatting to?
I've been told by one of my module tutors that ITS say quite specifically {but my phrasing is rough} that if you want to transfer files then MSN is a good option but if you want to transfer larger files then the use of peer to peer is recommended.
even if they are monitoring traffic, how can they distinguish between legal transfer of say, red vs blue or linux distributions and other transfers ? Surely they aren't allowed to spy like this just on the off chance of catching someone ... ?
so are they in beach 
??Well, I still maintain that the definition of peer to peer is a little loose. You could argue, on the lowest level, that technically everything on the internet is not peer to peer, since every connection(TCP or UDP) works between one machine acting as a server(listening) and another client machine connecting to it. At the other end of the definition scale I'd say a peer to peer system is one, like Gnutella, Kazaa etc, that don't require a central controlling server to operate. If I remeber correctly, the phrase 'peer to peer' came about after the fall of Napster to describe systems which were unlike Napster in the sense that they did not have a central site that could be shut down to kill the whole system.
And on the topic of ITS catching people using DC++. If looking inside packets is really a breech of their contract and confidentiality we must assume they 'catch' people by examining the ports they are using, and this certainly is not proof of any kind. The ports DC++ uses are not dedicated to it. What if you happen to be downloading a large file over FTP (this is entirely legitimate) and it chooses DC++'s port?
I'm just saying that ITS's rules for and treatment of all this seems to be a bit vague at the moment.
And on the topic of ITS catching people using DC++. If looking inside packets is really a breech of their contract and confidentiality we must assume they 'catch' people by examining the ports they are using, and this certainly is not proof of any kind. The ports DC++ uses are not dedicated to it. What if you happen to be downloading a large file over FTP (this is entirely legitimate) and it chooses DC++'s port?
I'm just saying that ITS's rules for and treatment of all this seems to be a bit vague at the moment.
Further to that, I've had a thought with regard to the university receiving complaints(are these rumours or verified now?) from companies about the university file sharing activity. Do the large internet backbone companies receive complaints like this, since they must carry vast amounts of P2P file sharing activity? Are the operators of London Telehouse expected to filter out illegal packets and disconnect those responsible? And if not does the responsibility usually fall on ISPs? I certainly haven't heard of any normal dial-up or broadband ISPs blocking ports or disconnecting people to stop illegal file sharing so why do ITS feel they have to? Is there something special about their arrangement that would leave them open to legal action for not stopping us?
nope the rumours are still RUMOURS no proof has been presented. That is exactly the point these letters are random and companies send them out to IPS's all over the country. Companies know filesharing happens and something like 1 in 10 of us download illegal content. The port blocking and restriction of service is invalid and should not be implemented. Back when i had BT as a ISP i thought there service was bad but they didnt stop people sharing files, whatever there nautre (illegal or not)?
Well no MSN IS NOT!!! a P2P app.. that is for sure.. it may in certain circumstances connect directly, but the term P2P is more specific to that.. it is defined by a group of apps that use the group of protocols inside the P2P group. these either use or dont use a server as a central meeting point and all transfers/connections are then direct. The main reason MSN is not considered P2P is its size of packets I believe. Should really look into the specific reason for its categorisation outside P2P..cocodude wrote:When you chat to someone on MSN, don't the chat messages (and file transfers) go directly to the person you are chatting to? I know this is how ICQ at least used to work (when it's not the case that both parties are firewalled). If so, MSN is P2P in the same way DC is P2P - you connect to a central server to get userlists and talk directly to other peers.echelon wrote:MSN on the other hand has nothing to do with P2P and uses a slightly different protocol. It also can make several connections, but often its bandwidth usage is far smaller..
Cocodude
I dont entirely agree with this.. I wouldnt consider the listening machine a server. Thats not the correct definition really.. in a server-client relationship both the client and the server are listening. Thus the argument doesnt quite hold tight.oliford wrote:Well, I still maintain that the definition of peer to peer is a little loose. You could argue, on the lowest level, that technically everything on the internet is not peer to peer, since every connection(TCP or UDP) works between one machine acting as a server(listening) and another client machine connecting to it.
Yes I believe u're right bout the time for the P2P definition hitting mainstream. I believe the term existed b4 that.. but it was after the fall of Napster that it got widely accepted and came to define that group of apps that u mention.oliford wrote:At the other end of the definition scale I'd say a peer to peer system is one, like Gnutella, Kazaa etc, that don't require a central controlling server to operate. If I remeber correctly, the phrase 'peer to peer' came about after the fall of Napster to describe systems which were unlike Napster in the sense that they did not have a central site that could be shut down to kill the whole system.
Very true.. but I'm not sure that its actually illegal or that ITS consider it illegal to monitor the traffic. They may have to accept that its illegal if ppl on the ResNet rise up and demand for proper terms, but right now ITS seems to decide wat goes and wat doesnt without anyone resisting.oliford wrote:And on the topic of ITS catching people using DC++. If looking inside packets is really a breech of their contract and confidentiality we must assume they 'catch' people by examining the ports they are using, and this certainly is not proof of any kind.
well FTP happens to always use the same port!! this being port 21.. so I dont think "it will ever just randomly choose another port!!oliford wrote:The ports DC++ uses are not dedicated to it. What if you happen to be downloading a large file over FTP (this is entirely legitimate) and it chooses DC++'s port?
I very much agree with u on that.. I think this is something that should be raised in Focus Group. They need to properly define their rules and regulations if they plan to be strict and enforce them. They also need to get a proper information system. As they suck majorly at informing their users of anything!! like a list of restricted subnets.. has that appeared yet??oliford wrote:I'm just saying that ITS's rules for and treatment of all this seems to be a bit vague at the moment.
Don't forget that these two protocols work on top of IP, which is peer-to-peer, as in a packet simply gets sent to a machine with no concept of server/clientoliford wrote:You could argue, on the lowest level, that technically everything on the internet is not peer to peer, since every connection(TCP or UDP) works between one machine acting as a server(listening) and another client machine connecting to it.
Cocodude
And who exactly defines P2P? ITS certainly don't. On a technical level there is no difference between MSN and DC++. The only real different is the MSN is not a file sharing application.echelon wrote:Well no MSN IS NOT!!! a P2P app.. that is for sure.. it may in certain circumstances connect directly, but the term P2P is more specific to that.. it is defined by a group of apps that use the group of protocols inside the P2P group. these either use or dont use a server as a central meeting point and all transfers/connections are then direct. The main reason MSN is not considered P2P is its size of packets I believe. Should really look into the specific reason for its categorisation outside P2P..
It does actually. The FTP 'conversation' is to the dedicated port 21 on the server and from a random port on the client. However, the FTP transfer is acheived by the client computer opening a listening socket on an arbitary port. The server is told the port number and connects back to it from port 20 on the server's end.echelon wrote:well FTP happens to always use the same port!! this being port 21.. so I dont think "it will ever just randomly choose another port!!
Yea, exactly. Do you think we can all agree there are at least a few issues with definitions now?cocodude wrote:Don't forget that these two protocols work on top of IP, which is peer-to-peer...