clements@bbnccq (09/11/85)
From: Bob Clements <clements@bbnccq.ARPA> Hi, Steve, First: Do I believe this? BITNET and UUCP to ARPANET by way of Berkeley in only 3 minutes? Far out! > Received: from BBNA.ARPA by BBNCCQ ; 11 Sep 85 10:03:47 EDT > Date: Wed, 11 Sep 85 10:00:24 edt Well, let me see if I can answer some of your questions. I'll CC this to the packet mailing list, in case anyone else can make use of the info, or wants to add better answers. > I have seen some of these systems referred to as bulletin boards. Does > that mean that notes of local interest can be posted and made available > for all to see? There are other systems than the W0RLI ones, so answers for them may be different. But for the W0RLI systems: There are three main functions: Mail handling, File handling, and Gatewaying. Mail consists of short messages from one Amateur to another or to the National Traffic System (NTS) or to an address such as "ALL" or "NEPRA" or "GLBERS" or whatever. Mail can be automatically forwarded from one PBBS to another. Commands for mail messages allow you to send it, read it, kill it, and list messages by various categories. File handling commands allow text files to be uploaded and downloaded, and directory listings to be made. Files are standard CP/M-80 files. These are typically network maps, flea market listings, new user info, hints and kinks, short BASIC programs, etc. They are not automatically forwarded among PBBSs. Gateway operation connects two RF paths. Typically one is on two meters and the other is on 20 or 30 or 40 meters. In some cases, the two paths are on two different VHF/UHF bands, and there are some that go between two different two meter frequencies. This latter case gets into a long discussion of congestion control which I won't go into here. The common case of HF gatewaying allows a local 2 meter user to talk to hams in other parts of the country by using the gateway station's HF gear. It also is used by the mailbox itself for forwarding mail to distant areas. > Logging in was mentioned in the list of updates. Do > users need accounts to use the system or is the login merely to identify > who the current user of the system is? Logging of all activity is done for record keeping, analyzing the network performance and general interest. No "login" is required by the users. > Can more than one person use the system at a time? The system was built on the TAPR TNC-1 which only allows one connection at a time. The WA8DED replacement code for the TNC-1, and the TNC-2 allow multiple connections at once. Hank is thinking about allowing more than one connect at a time, but it would be a huge rewrite. We are considering whether it might be better to put this off until the code is moved to a new hardware base, such as a cheap IBM PC clone. In any case, it isn't here yet and won't be for a while. > I have several questions about mail forwarding. Does the complete > address of the recepient need to be specified or does the system have some > type of routing table? The system has a routing table. It is typically not a complete list of all the packeteers in the world. That would be huge. In practice, it includes all the known mailboxes in the world, plus the users of "nearby" mailboxes. Users can send messages to "W6XYZ @ KD6SQ", for example. I probably don't have W6XYZ in my list, but I do have KD6SQ. I get a lot of traffic for K1OJH, president of NEPRA, so I have K1OJH at W0RLI in my table, because my users are likely to forget to include the "@ W0RLI" when they send mail to K1OJH. > What are the advantages of sending mail via > autoforwarding vs. digipeating the message to the closest mailbox to the > destination? Digipeating a long distance is a bad idea in general. The reason is that the probability of any given packet failing to get to the other end deteriorates exponentially with the number of digipeaters. This leads to many retransmissions, wasting channel capacity. There is no hop-by-hop retransmission and acknowledgement when using digipeaters. Using the forwarding of PBBSs, each PBBS along the way gets acknowledgement of the packets and of the message. It can also retry from time to time, thus allowing forwarding through a path that is not open 24 hours a day. In fact the entire path may never have been available all at once. All that is needed if for each piece to be available sometime. > Does the mailbox hold mail for anyone or just those > known to the system? Actually, the algorithm is the inverse of this. It forwards all mail that it knows how to forward. If it has no path in the routing table for a message, that message stays where it is. > I would also be interested in seeing a transcript of a session with a > W0RLI system if you have the capability to capture text. Sorry, I don't have an easy way to do that from here. The commands were described above. In addition, when you first sign on, it greets you and tells you of any new mail addressed to you. > I appreciate any information you could provide. There is some interest > in packet in this area (Central Penna.) but no activity that I know of. > I am trying to convince a club here to put up a mailbox system or at > least a digipeater. The more I know about the capabilities of the W0RLI > system, the better my case for installing one will be. Great! Do it! Pat the Nittany lion for me. I used to live in Boalsburg when I was a wee tad. > Finally, I have read somewhere that there was a packet group forming in > the Eastern Penna./MD/DEL area to coordinate networks -- or something > along those lines. I can't find the reference to it anymore. Do you > know what group I'm talking about? If so, do you know how I can get in > touch with someone in that group? I'm not sure exactly which group this is. I know AMRAD is involved in that sort of thing. Also, the Gateway newsletter from ARRL carries news of that sort. Gateway is sometimes posted to this net. (Personally, I refuse to subscribe to Gateway and QEX. I believe the info belongs in QST where it will benefit the hobby by wide exposure. The fragmentation that the ARRL is doing by making all these "newsletters" instead of making them columns in QST is harming our hobby. But that's another soapbox.) > 73, > Steve Fine > UUCP: allegra|ihnp4|akgua !psuvax1!gondor!fine > ARPANET: fine%psuvaxg.bitnet@wiscvm.arpa 73, Bob Clements, K1BC UUCP: {ihnp4,decvax,linus}!bbncca!clements ARPANET: clements@bbn.arpa Everything mentioned above is probably the trademark of somebody. The views expressed probably are different from those of my employer, BBN, which is heavily into non-ham networks.