This document is a preformatted alternative to the NEDA Recommended BPQ Parms document using tables, intended for those who use web browsers that cannot handle tables. However all links from other documents will go to the tables version. If you link to other documents from here, you must use your browser "back" button to return to this document.
Only the parameters that should be adjusted from the values in the supplied default BPQCFG.TXT are mentioned. You must still enter all the parameters needed for your particular system in the BPQCFG.TXT file. Consult the BPQ PORTS.DOC for required parameters. Just try to make sure that the following parameters are adjusted to the values shown.
Note: Any changes since the
May 1995 meeting are detailed at the end of this document.
OBSINIT=5 INITIAL OBSOLESCENCE VALUE OBSMIN=3 MINIMUM OBSOLESCENCE TO BROADCAST NODESINTERVAL=15 NODES BROADCAST INTERVAL IN Minutes IDINTERVAL=0 We don't need IDs. L3TIMETOLIVE=13 MAX L3 HOPS. L4RETRIES=2 (1) LEVEL 4 RETRY COUNT - Does 1 actually work? L4TIMEOUT=180 LEVEL 4 TIMEOUT in seconds L4DELAY=10 LEVEL 4 DELAYED ACK TIMER in seconds L4WINDOW=2 DEFAULT LEVEL 4 WINDOW SIZE (L4 MAXFRAME) MAXNODES=100 Maximum known nodes in node table MINQUAL=50 MINIMUM QUALITY TO ADD TO NODES TABLE. Note:this is not the same definition as the MINQUAL in the ports configuration section. Also it is overridden by QUALITY in the ports section. BBSQUAL=128 BBS Quality relative to NODE - used to limit 'spread' of the BBS through the network to your required service area. Start with 128 and adjust so that BBS shows ONLY at the nodes normally used by its users. IE: At your stack and at the most one visible hop away.
PACLEN=236 MAX PACKET SIZE in bytes. More would fragment NET/ROM frames.
T3=320 LINK VALIDATION TIMER in seconds (5 MINS) IDLETIME=7200 IDLE LINK SHUTDOWN TIMER in seconds (2 hrs)
HIDENODES=1 # Nodes only listed with N * command
These parameters are for a visible port where live keyboard
stations access the network and access resources over the network. No station
is heard on-channel by the user port that transmits more than 3K/hour average
or 300K/Month. No node-to-node communications on this port. No node broadcasts
out on this port. All node broadcasts in on this port are ignored.
PORT ID=USER PORT This ID will show in response to Ports command. Edit to show frequency or purpose of port. QUALITY=0 Inhibits node broadcasts and L3/L4 connects on this port. MAXFRAME=1 for 1200 bps. =4 for 9600 bps (See note #9) TXDELAY=350 Milliseconds SLOTTIME=200 Milliseconds PERSIST=64 FRACK=6000 Milliseconds(See note #8) RESPTIME=500 Milliseconds RETRIES=10 PACLEN=236 DIGIFLAG=0 ENDPORT
These parameters are for a visible port hearing other nodes, servers or any station generating large amounts of data. It probably would also be plagued by serious HTS (Hidden Transmitter Syndrome) effects. Affectionately known as a "ZOO" channel.
PORT ID=NON-IDEAL USER PORT This ID will show in response to Ports command. Edit to show frequency or purpose of port. QUALITY=0 Inhibits node broadcasts and L3/L4 connects on this port. MAXFRAME=1 TXDELAY=350 Milliseconds SLOTTIME=200 Milliseconds PERSIST=64 Or even 40 for extremely congested channels. FRACK=15000 Milliseconds. This is the price you pay for a zoo channel. Depends on TNC type. (See note#8) RESPTIME=500 Milliseconds RETRIES=10 PACLEN=236 More would be subject to fragmentation by NETROM DIGIFLAG=0 Digipeat not commonly used today. ENDPORT
These parameters are for a visible non-2m port that acts as a hopping point between networks. Accepts node broadcasts from the other network but only broadcasts itself. The purpose of this is to allow two networks that have conflicting parameters to meet, allowing users and services to cross over, but without having the node lists intermingle. We're never going to get a gateway defined exactly because they will be customized for the various circumstances every time but this is the general idea.
PORT ID=GATEWAY PORT This ID will show in response to Ports command. Edit to show frequency or purpose of port. QUALITY=50 Inhibits propagation of any received node. MAXFRAME=1 (See note #9) TXDELAY=xxx Milliseconds - Set depending on Radio and parameters of the other networks that are gatewayed into. SLOTTIME=200 Milliseconds PERSIST=64 Depends on number of station on channel - 256/(N-1) FRACK=12000 Milliseconds- Adjust according to other stations on port.(See note#8) RESPTIME=500 Milliseconds RETRIES=10 PACLEN=236 More would fragment in NETROM DIGIFLAG=0 Digipeat is not commonly used today MINQUAL=210 This effectively limits node broadcasts (on the port directed towards the other network) to this node information only. ENDPORT
These port parameters are for a port connected to a NETROM/TheNET Node RS-232 port or to a diode matrix. It assumes that there will be no feedthru of Node information from any other ports on the BPQ switch. If there are nodes fed thru to be broadcast on this port, then Quality should be set to 161 on both ends of the NETROM link (See note #7). Also make sure that this port is actually connected to a matrix or NETROM node (See note #11).
PORT ID=NETROM CONNECTION This ID will show in response to Ports command. Edit to show frequency or purpose of port. QUALITY=203 Assumes no feedthru of node information form other BPQ ports (See note #7) MAXFRAME=1 (See note #9) FRACK=1000 Milliseconds. Not important-few retries. RESPTIME=0 Milliseconds (See note #10) RETRIES=10 PACLEN=236 More would fragment in NETROM FULLDUP=0/1 0 for diode matrix, 1 for connection to a single NETROM/TheNET node RS232 port. DIGIFLAG=0 Digipeat is no longer commonly used. QUALADJUST=100 Equivalent to X1J Alternate Broadcast Algorithm (See note #1) ENDPORT
BPQ Ports with a direct radio connection are usually interfaced with a TNC
operating in KISS mode or with an internal HDLC card like a DRSI card. The
following are for KISS TNCs. Where other interfaces are used, use these
parameters as guidelines.(See also: Shared KISS
These port parameters are for a port used as a dedicated point-to-point link in a network using a TNC with BPQKISS EPROM installed or a Kantronics TNC with special KISS eprom. Use of standard KISS TNCs should be discouraged wherever possible.
PORT ID= DEDICATED POINT-TO-POINT PORT This ID will show in response to Ports command. Edit to show frequency or purpose of port. TYPE=ASYNC PROTOCOL=KISS Protocol type CHANNEL=A Or B,C,..according to how the BPQKISS EPROM was burnt. QUALITY=203 or 161 Use 203 if you are not broadcasting nodes from other ports. Use 161 if you are broadcasting nodes from other ports. Node at other end of this link should also have HDLC quality set to the same quality as this port.(See note#7) MAXFRAME=1 (See note #9) TXDELAY=xxx Milliseconds - Set to value appropriate for the radio used. SLOTTIME=10 Milliseconds. Se also:Shared KISS Parms PERSIST=255 See also:Shared KISS Parms FRACK=4000 Milliseconds. (See note #8) See also: Shared KISS Parms RESPTIME=200 Milliseconds RETRIES=10 PACLEN=236 More would fragment in NETROM DIGIFLAG=0 Digipeat is not commonly used today KISSOPTIONS=POLLED,CHECKSUM,ACKMODE Important for proper operation of BPQKISS port VALIDCALLS=<callsign1,callsign2,...> Used instead of locking ROUTES. See note #6. ENDPORT
These port parameters are for a port used as a dedicated
point-to-point link in a network using a TNC and standard KISS mode where it is
not possible to use BPQKISS mentioned above. Standard KISS TNCs should only be
used if it is impossible to use BPQKISS (or equivalent KISS using handshaking on
the serial connection).
PORT ID= DEDICATED POINT-TO-POINT KISS PORT This ID will show in response to Ports command. Edit to show freq or purpose of port. TYPE=ASYNC PROTOCOL=KISS Type of protocol QUALITY=203 or 161 (See note #7) Use 203 if you are not broadcasting nodes from other ports. Use 161 if you are broadcasting nodes from other ports. Node at other end of this link should also have RS-232 quality set to the same quality as this port. MAXFRAME=1 (See note #9) TXDELAY=xxx Milliseconds - Set to value appropriate for the radio used. SLOTTIME=10 Milliseconds. See also: Shared KISS Parms PERSIST=255 See also: Shared KISS Parms FRACK=4000 Milliseconds.(See note #8)See also:Shared KISS Parms RESPTIME=200 Milliseconds RETRIES=10 PACLEN=236 More would fragment in NETROM DIGIFLAG=0 Digipeat is not commonly used today VALIDCALLS=<callsign1,callsign2,...> Used instead of locked ROUTES. See note#6. ENDPORT
On the last two KISS port lists, if the port is used on a HTS (Hidden
Transmitter Syndrome) Free SHARED channel, then the following
parameters are to be used instead. A SHARED HTS Free channel would be one where
more than two (2) stations, all of whom can hear each other well, are linked or
where a regenerating digital repeater is used.
FRACK=8000 Milliseconds (See note #8) PERSIST=xx Adjust according to number of stations PERSIST=256/(N-1) SLOTTIME=200 Milliseconds QUALADJUST=100 Enables equivalent to X1J alternate broadcast algorithm. (See note #1).
If you do not need to transmit UI frames on the radio port, we recommend that the BPQ switch be connected to a diode matrix and all radio ports operated as X1J nodes using regular TNCs. Even when you have only one radio port, it should be connected as a TheNET node with a "NETROM" cable linking the serial port and NETROM protocol used in the BPQ switch. Then the BPQ becomes simply a multi-connection interface for the BBS or other application. We recommend using a BPQ/RS-232 timeout timer to prevent matrix lockups should the computer crash.
Locking ROUTES and setting default port quality to 0 (a common network management practice with TheNET nodes) will not work with BPQ. Setting QUALITY to 0 disables the node broadcasts from that port AND it ignores all incoming node broadcasts. Setting QUALITY to a low non-zero value like 1, even if it is lower than MINQUAL (in Network System Parameters) still results in the neighbor nodes being entered in the node list. This is not documented but comes from my own observations. The only way to prevent connects from uncontrolled stations is to use the VALIDCALLS parameter mentioned above.
BPQ has different hardware than a dedicated hardware TNC node. One BPQ switch (containing 1 CPU) will do the job of 2 TNC nodes (containing 2 CPUs) on each path through the node stack. The quality "decrement" through 2 TNCs is equivalent to a quality of 161 (203/256 x 203/256 = 161/256). So to have the BPQ reflect the same parameters as a TNC node stack the Quality would have to be set to 161. However this only affects node listings that pass through the BPQ from one port to another. A user port is usually configured with QUALITY=50 (and no nodes broadcasts) so that it will not propagate nodes heard on that port and so this quality argument does not affect it. Therefore in a BPQ switch that does not pass any node information from one port to another, QUALITY=203 is appropriate (since it is functionally equivalent to one TNC). If node information is propagated from one port to another, then use QUALITY=161.
Another special case is a BPQ switch where all the ports are interfaced to individual TheNET nodes. One purpose of such a "node stack" would be to allow many more circuits (TheNET is generally limited to 24) through a busy Hub node. In this special case, each path contains three CPUs (one BPQ and two TNCs). We suggest that QUALITY=228 on each end of all of the BPQ<>NETROM links would achieve an overall quality = 161.
Whatever the QUALITY assigned to a network port, the quality on the node or BPQ port at each end of a network link should be the same. This will avoid "non-symmetrical" routes which show further in one direction than the other and may not be connectable from the extreme ends.
On the other extreme, a BPQ port feeding a NETROM node serial port or a diode matrix, will not have any significant retries so the FRACK can be set to 1 second. Other types of ports would naturally fall somewhere in-between these extremes.
Added on top of this dilemma is a lack of knowledge on just how the computer handles FRACK. This will require a series of appropriate experiments before we can choose the suitable values for FRACK under differing conditions. We already know how it handles FRACK in a regular KISS mode TNC. What we need to know is the operating mode for the following:
a/ TNCs operating BPQKISS with KISSOPTIONS=POLLED,CHECKSUM,ACKMODE. b/ TNCs operating in DED HOST mode and G8BPQ HOST mode. c/ Operation with internal HDLC cards like DRSI (may be the same as /b ??). d/ Anything I forgot???
Meanwhile until we can get results on some experiments, let's set FRACK at 6 seconds (6000 milliseconds) on a quiet LAN user port and dedicated links running KISS mode, 12 seconds on a busy LAN USER port and 15 seconds on a "ZOO" channel. If you are running regular KISS mode, please convert to BPQKISS which at least allows the computer to monitor the outgoing transmit buffer. Better still if you can, convert the TNC to a TheNET node and link the BPQ using NETROM protocol. (This is not possible if running TPK or other UI frames on the radio port.) The best situation would be to operate all ports in your facility as TheNET nodes. Then use the BPQ switch linked to a diode matrix solely as a multiconnect interface with an application like a BBS.
NEDA's policy is that all users have an equal opportunity to access the available resources of the network. On a user port no- one should have to wait a long time to get a frame transmitted or to receive a frame from the node or server. This is achieved by setting L2 MAXFRAME=1 and setting appropriate persistence and slottime parameters to allow opportunities for transmission to the node. At 1200 bps one frame + TXD typically takes two seconds to send. Assuming say five users on the channel, most of whom are receiving information from the node or server, each user should not have to wait more than 10 seconds per frame. If the MAXFRAME was set to 4 for example, some users might have to wait as long as 30 seconds for their share. Not very fair. Note: This MAXFRAME value only affects transmissions made by the node or switch downlinking to the user. All uploaded frames are controlled by the MAXFRAME parameter in the user's TNC.
The opponents to the MAXFRAME=1 would say that may be fine for 1200 bps ports but for 9600 bps ports, the value should be higher. After discussing it at the last meeting, I proposed that for higher speed ports, higher MAXFRAME values were appropriate so long as any one transmission to a user did not exceed say 2 seconds. MAXFRAME=4 or even =6 on 9600 bps user ports would meet this criteria. MAXFRAME=3 would be appropriate on a 4800 bps port.
MAXFRAME settings on the backbone links are another matter. NEDA has again held that MAXFRAME=1 insures equal sharing of network resources and has results of early experiments that supports the claim that the overall throughput of the network is higher at MAXFRAME=1. Opponents counter that this is the result of a large number of slow 1200 bps links in our network and if we were to install all high speed links, the NEDA claims would be proven wrong. At this point however, there is no solid experimental evidence to prove either way. There is great need to research this important matter. Meanwhile we continue to recommend MAXFRAME=1 because we know it works and has no serious detrimental effects on the network (like totally locking up).
It is my opinion that one of the most important factors in overall network performance of TheNET networks is how "chokes" are handled and the effect of chokes on network data flow. It was my impression (on reading the original NETROM documentation) that if a NETROM L4 link chokes due to one circuit being unable to deliver its data, then all the circuits being handled on that L4 link are also stopped although they may well have clear destinations that are not affected by the choke. However, as a result of a recent "accidental" experiment, this was proven not to be true, at least not for TheNET and NOS systems (the "experiment" involved a circuit through more than 20 TheNET nodes - both X1J and 2.0x types - ending in a JNOS converse node system). Even though that one circuit was totally choked, other streams moved through parts of the same path without hindrance. A similar experiment involving a BPQ switch has yet to be run.
If you guys have any better ideas, let's hear them. Meanwhile all of us that run BPQ can check out these above-mentioned parameters for serious problems.
Compare with the NEDA X1JR4 Recommended Node Parms.