(The explainations are written for the average user. If you would like a more in-depth answer, please email us. ) Is Jungle Monkey peer-to-peer? Yes. Jungle Monkey is decentralized; there is no central server. How do Jungle Monkey channels work? Jungle Monkey channels are built upon multicast. Multicast lets you send one thing to many computers at once. Computers join a "multicast group" and can then send to or receive from that group. The alternative is to use unicast, which lets you send one thing to one computer. However, if you needed to send something to multiple computers you would need to send it multiple times. A channel in Jungle Monkey is a multicast group. People send announcements for their files to the group. Announcements are sent periodly, so it may take a while before you see announcements for a channel you just joined. How are files transfered in Jungle Monkey? When you download a file, you first connect to rendezvous server. The rendezvous server has a list of mirrors of that file. JM then figures out which mirror is closest and downloads the file from that mirror. Jungle Monkey will eventually support simultaneous downloads from multiple sources. What is end-host multicast (EM)? The variant of multicast Jungle Monkey uses is end-host multicast (as opposed to IP Multicast or IPv6 Multicast - see below). End-host multicast organizes a bunch of computers together in a tree so that they can share data efficiently. An end-host multicast tree is similar to telephone tree. A telephone tree is a tree of people with phone numbers used to distribute information. For example, I might be organizing a party and distribute a telephone tree to my friends (see figure below) so I can keep them up-to-date with party plans. The telephone tree may say if David calls Alice and Bob, Alice should call Carl and Dana and Bob should call Elijah and Fred, then Carl should call Gary and Hilda, and so on. Each person is responsible for calling two people. Ultimately, everyone who is in the telephone tree will receive the information and everyone had to call at most 2 people. End-host multicast is not like a telephone tree in that the tree is self-organizing. The means that when you join the group, your computer finds the closest computer and makes that computer your parent in the tree. Also, other computers may make your computer their parent. There are different variants of end-host multicast. The protocol Jungle Monkey uses is called the "Banana Tree Protocol". Why don't you use IP Multicast? IP Multicast is an extension of the Internet Protocol, the protocol that make the Internet work. It supports multicast at a low-level protocol and is, in theory, more efficient than End-host Multicast. However, IP Multicast is not widely available. In fact, the original version of Jungle Monkey used IP Multicast, but we abondoned it because we couldn't find any users who had it. Why not use IPv6 Multicast? IPv6, the next generation of the Internet Protocol, supports multicast. We will consider using it once IPv6 is more widely used, but don't hold your breathe. How does searching work? Searching is done in "search groups" and each search group has a multicast group. To search, a query message is sent to the group. If another member has a matching file (or channel, search group, or chat group), they will send a match message to the group. Members may cache previous match messages and use them to answer queries. We are currently researching new distributed keyword search architectures. How do I limit the amount of bandwidth that Jungle Monkey can use? The end host cannot currently limit the amount of bandwidth used or number of connections made. Jungle Monkey uses TCP, so the congestion control mechanisms that most TCP implemenations use should be sufficient to avoid congesting the network. Also, if you are a network administrator, there is something else you can do to lower the bandwidth used by JM. When file transfers are made, the ToS bits on the packets are set to IPTOS_LOWCOST. Network administrators may be able to set queueing policies based on this so that file transfers receive a lower priority than other network traffic. (If you know how to do this or have a reference on how to do this, please send it to me so that I can include this information.)