Hi Paula and group I'm no expert in this but I'll try and explain how I set up the IP routing at GB7CP which is a 7 port standalone subrouter with 6 radio ports (currently only 4 of them carry IP traffic directly) and 1 ethernet port to connect to 2 other PCs running windows and JNOS on a local LAN This subrouter works in conjunction with the linux hub gb7cip that provides all the services. I shall keep this simple and deal with routing entries that are permanently coded and are using amprnet addresses though the same principles can be extended to provide connection via the internet but I have no personal experience of setting that up. There are mechanisms for arp entries to be created but as we work with fixed networks it makes sense to code these in as permanent entries First a couple of simple points 1) IP addresses are 32 bit binary numbers usually written for us humans in the form of the familiar dotted quad notation 44.131.244.60 Each number representing 8 bits of the whole address. Each of the 4 digits from right to left addresses an increasing sized block of addresses. Starting with individual addresses with the right hand digit and progressing to larger blocks covering larger geographical areas Thus I'm address 60 in block 244 (North Surrey area) in block 131 (British Isles) in block 44 (amateur radio) 2) Xrouter requires 2 entries in its IPROUTE.SYS file to make IP routing work First an ARP entry This is roughly equivalent to the ROUTE entry for Netrom in that you simply need one entry for each partner that you directly link to.This entry will map the partners IP address to its callsign or hardware address. Then if xrouter is required to send a packet to a radio linked partner it will wrap the IP frame in an AX25 packet addressed to the partners callsign or in the case of an ethernet connection via local LAN it will wrap it in an ethernet packet and send it to the hardware address of the ethernet card. Second an IP ROUTE entry This is more like the Netrom NODE table entry in that for a packet destined for a given IP address it tells xrouter which port to transmit the packet on and which gateway IP address to route the packet via. But here it does not need to be an individual entry for each address it can be specified as a block or range of addresses and it specifies what type of packet that partner is expecting. The size of the block of IP addresses that are being routed is set by a MASK parameter that is a number 0 to 32 which masks off the bits of the address and allows complete control of which addresses are routed to where. For example a mask of 32 specifies a single address, 31 a pair of addresses 30=4 addresses, 29=8,28=16,27=32,26=64,25=128, 24=256 etc. Thus a common mask is 24 this will allow a whole block of 256 addresses to be routed to a HUB e.g. all the addresses in subnet 244 could be routed with a single entry of ROUTE ADD 44.131.244.0/24 (mask of 24) Thus with relatively few entries the whole internet address space may be routed. This means that you do not need to hold routes to every individual station you only need that detail for your immediate area, outside that you need to route in larger and larger blocks. For example if you have a well connected gateway such as GB7BBC near by you might route all traffic outside the UK's 131 country block to him for distribution. This way from the reasonably simple IPROUTE.SYS in my xrouter I am able to route directly to individual users in the USA or VK A usefull little check program written by G4POI is on the Kent IP Group's JNOS distribution disc in the C:\NOS\UTILS directory and is called ROUTE.EXE and simply tells you what range of addresses each address / mask combination gives you and stops you making silly errors. Lets now look at my copy of IPROUTE.SYS for GB7CP ============================================================= ; IPROUTE.SYS Last modified: 11/07/02 ; ; IP routing tables for GB7CP AX25/IP router. ; Ports are: ; 1 backbone to GB7CIP (NETROM +IP) (G8DTQ-10 + 44.131.244.48) ; 2 Link south to GB7WSX (IP ONLY) (GB7CP-10 + 44.131.244.12) ; 3 Link NW to GB7DID (Didcot) (NETROM +IP)(GB7CP-9+44.131.244.13) ; 4 Link SE to GB7SXE (NETROM ONLY) (GB7CP-11) carries IP over netrom ; 5 User Access 144.8875 Mhz (L2 ONLY +IP)(GB7CP-2 44.131.244.15) ; 6 6 mtr port unused at present ; 10 Ethernet Lan ; ; ; d Datagram (use on very good quality links only) ; v Virtual circuit (better for links with retries) ; n Netrom (for "tunnelling" through netrom-only networks) ; e Encapsulated (e.g. ham IP carried by Internet IP) ; ; ; ROUTE [ [] ] ; =============================================== ; (mode defaults to datagram) ; ; Try all unknown routes via ; route default 10 * d ; ; ; Specifying a gateway address of 0.0.0.0 or just "*" ; will cause the host to be routed direct. ; ; ROUTE ; ===================================================== ; ; Test to Didcot via 432.625 9600baud route add 44.131.154.101/32 * 3 d ;Didcot test route add 44.131.244.58/32 44.131.154.101 3 d ;Catrad at Shilton ; ; Users via 2 mtrs route add 44.131.236.150/32 * 5 d ;User G0LEH route add 44.131.237.11/32 * 5 d ;User M0BYM route add 44.131.244.57/32 * 5 d ;User G7OBF route add 44.131.244.56/32 * 5 d ;User G8DTQ test ; ; Internal Ethernet Lan route add 44.131.244.59/32 * 10 d ;my lounge win98 PC route add 44.131.244.60/32 * 10 d ;shack nntp JNOS cache ; ; Local users with routers using a pair of IP addresses route add 44.131.241.120/31 44.131.241.120 5 d ;User G3DPW route add 44.131.244.20/31 44.131.244.20 5 d ;User G3TWJ ; ; Routing south via GB7WSX route add 44.131.244.208/28 44.131.245.97 2 d ;244.208-223 via WSX route add 44.131.244.64/26 44.131.245.97 2 d ;244.64-127 via WSX route add 44.131.244.128/26 44.131.245.97 2 d ;244.128-191 via WSX route add 44.131.220.0/24 44.131.245.97 2 d ;220 subnet via WSX route add 44.131.245.0/24 44.131.245.97 2 d ;245 subnet via WSX route add 44.131.246.0/23 44.131.245.97 2 d ;246+247 subnets via WSX route add 44.131.216.0/22 44.131.245.97 2 d ;216-219 subnets via WSX ; ; route add 44.0.0.0/8 44.131.244.62 1 d ;default route via CIP ; ; ; ; ARP ; ========================================================================== ; arp add 44.131.244.59 ether 00:00:E8:9E:10:54 ;my lounge win98 PC arp add 44.131.244.60 ether 00:00:E8:EF:05:0B ;my Shack DOS PC ; arp add 44.131.244.62 ax25 G4APL-5 ; arp add 44.131.245.97 ax25 GB7WSX-4 ; arp add 44.131.154.101 ax25 G1SSL-1 ; ; Users via 2 mtrs arp add 44.131.236.150 ax25 G0LEH-5 arp add 44.131.237.11 ax25 M0BYM-5 arp add 44.131.244.57 ax25 G7OBF-5 arp add 44.131.244.20 ax25 G3TWJ-5 arp add 44.131.241.120 ax25 G3DPW-5 =================================================== That's the whole of it (its arranged in ascending order of mask size as earlier versions of xrouter picked the first match found but this is fixed in later versions 173a onwards and could be in any order) Now lets look at the sections of IPROUTE.SYS Starting with route default 10 * d This acts as crude firewall for me and routes any address not specified in the remaining table (i.e. any non-amateur address) to my ethernet LAN where is gets dumped as I have no connection to the internet so thats routed the vast majority of the internet address space to a bit bucket. In my case it stops all those annoying windows applications trying to phone home via my local amprnet hub. So we only now have the amateur radio "44" addresses left to deal with. -------------------------------------------------------------- Next come the individual addresses masked with the full 32 bits These first two are just test routes to DIDCOT's xrouter as no official IP routing goes this way at present, the entry for 244.58 is for our tempory radio camp thats just finished and used Didcot as a route back to our hub these are purely for testing ; Test to Didcot via 432.625 9600baud route add 44.131.154.101/32 * 3 d ;Didcot test route add 44.131.244.58/32 44.131.154.101 3 d ;Catrad at Shilton ; ; --------------------------------------------- Next come the individual users ; ; Users via 2 mtrs route add 44.131.236.150/32 * 5 d ;User G0LEH route add 44.131.237.11/32 * 5 d ;User M0BYM route add 44.131.244.57/32 * 5 d ;User G7OBF route add 44.131.244.56/32 * 5 d ;User G8DTQ test ; ---------------------------------------------- These entries support my 2 other machines ; Internal Ethernet Lan route add 44.131.244.59/32 * 10 d ;my lounge win98 PC route add 44.131.244.60/32 * 10 d ;shack nntp JNOS cache ----------------------------------------------- As we have been exprimenting with users accessing amprnet sites using windows IE and OE tools these two entries route pairs of adjacent addresses using a 31 bit mask to users that have a JNOS box routing out for their windows machines ; ; Local users with routers using a pair of IP addresses route add 44.131.241.120/31 44.131.241.120 5 d ;User G3DPW route add 44.131.244.20/31 44.131.244.20 5 d ;User G3TWJ Next comes the main IP routing that I handle ; Routing south via GB7WSX route add 44.131.244.208/28 44.131.245.97 2 d ;244.208-223 via WSX route add 44.131.244.64/26 44.131.245.97 2 d ;244.64-127 via WSX route add 44.131.244.128/26 44.131.245.97 2 d ;244.128-191 via WSX route add 44.131.220.0/24 44.131.245.97 2 d ;220 subnet via WSX route add 44.131.245.0/24 44.131.245.97 2 d ;245 subnet via WSX route add 44.131.246.0/23 44.131.245.97 2 d ;246+247 subnets via WSX route add 44.131.216.0/22 44.131.245.97 2 d ;216-219 subnets via WSX ; These route all the subnets that are reachable to the south of me via GB7WSX the comments explain the ranges of address that these apply to ------------------------------------------------ And lastly everything else for the amprnet is routed to my local linux hub gb7cip route add 44.0.0.0/8 44.131.244.62 1 d ;default route via CIP This routes all addresses in the 44 range including all addresses to the north,east and west of G and the rest of the world via the gb7bbc gateway all of that is handled by the linux router The gateway port of which is 244.62 ----------------------------------------------- Lastly lets deal with the ARP entries. There is one for each individual partner that GB7CP communicates with. The entries require IP address, type of packet that the IP frame will be wrapped in and callsign including SSID or MAC address of the ethernet card. ; arp add 44.131.244.59 ether 00:00:E8:9E:10:54 ;my lounge win98 PC arp add 44.131.244.60 ether 00:00:E8:EF:05:0B ;my Shack DOS PC ; arp add 44.131.244.62 ax25 G4APL-5 ;Gateway port of gb7cip ; arp add 44.131.245.97 ax25 GB7WSX-8 ;Hub in Crawley ; arp add 44.131.154.101 ax25 G1SSL-1 ;Hub in Didcot ; ; Users via 2 mtrs users port arp add 44.131.236.150 ax25 G0LEH-5 arp add 44.131.237.11 ax25 M0BYM-5 arp add 44.131.244.57 ax25 G7OBF-5 arp add 44.131.244.20 ax25 G3TWJ-5 arp add 44.131.241.120 ax25 G3DPW-5 ------------------------------------------------- I hope thats of some use to those struggling with setting up IP routing just remember if it doesn't work then you've done something wrong! It will almost certainly be simple and obvious ....but only after you've spent hours tearing your hair out. My simple rules would be ... 1 make sure you have a correct ARP entry for each partner or machine that you make a direct connection to 2 make sure you have a logical routing entry for every possible Internet address so you know precisely where every packet will be sent. If your confused pretend you're standing in the centre of xrouter in question with all your ports around you and make sure that you're routing entries squirt your intended addresses or address ranges out of the correct port whichever that might be and that the returning packet is returned to the user. This isn't as bad as it seems as even the most complex amprnet router will only have a relatively small number of ports in and out. You need a clear picture of those systems around you and you need to know which subnets they can route to and you need to agree with all your partners whats going where. This is not meant to be an complete guide its just the bits I've learnt from experience so if anyone can fill in any more aspects or correct any points please feel free to do so as I'm always looking to learn more. 73 de Bryan g0syr.ampr.org [ 44.131.244.60 ] Amprnet mail g0syr@g... AX25 mail G0SYR@G...#32.GBR.EU Internet Mail g0syr@b...