Speaking of TCP/IP ...
 
I have a requirement to setup subnets on our internal lan and at our remote loctions.
Can somebody tell me what the implications are for units on different subnets connected
on the same lan without an interventing router or bridge?  Is this a valid
configuration?
 
We have a mix of HP3000/9xx, HP9000/8xx, WinNT 3.51 and Win95 machines along with a
Cisco 2100 and a Livingston PM.  Our remotes sites have WinNt 3.51 and Win95 and will
be using RAS to connect over a high speed serial link using PPP.
 
Because of the small sizes of each subnet I have tentatively chosen to go with a subnet
mask and ip addressing scheme outlined below:
 
255.255.255.240         16 subnets      15x2; 16x14
                        0 and 255 are reserved addresses
                        subnet 0 host addresses 1 to 15
                        subnet 1 host addresses 16 to 31
                        subnet 2 host addresses 32 to 47
                        subnet 3 host addresses 48 to 63
                        subnet 4 host addresses 64 to 79
                        subnet 5 host addresses 80 to 95
                        subnet 6 host addresses 96 to 111
                        subnet 7 host addresses 112 to 127
                        subnet 8 host addresses 128 to 143
                        subnet 9 host addresses 144 to 159
                        subnet 10 host addresses 160 to 175
                        subnet 11 host addresses 176 to 191
                        subnet 12 host addresses 192 to 207
                        subnet 13 host addresses 208 to 223
                        subnet 14 host addresses 224 to 239
                        subnet 15 host addresses 240 to 254
 
There will be two or possibly three physicall distinct areas of lan traffic.  The outer
ring will consist of our cisco router, followed by a filtering i486 based gateway
machine controlling Internet access to  the perimeter lan.  This lan will have an
HP9000/8xx bastion/proxie server, the Livingston Port Master and one or two victem
machines followed by another i486 gateway/fliter to the inner Lan.
 
The inner lan will have another HP9000/8xx, our HP3000/9xx and all of our internal
workstations along with another Livingston PM for internal use.  For historical
reasons, it is apparently necessary to support two different subnet address groups on
the inner lan along with the external subnet traffic comming in over the internal
portmaster.  Will this cause a problem?
 
DNS for the entire network is supported on the inner 9000.  The HP3000 has telnet
connections made to it from workstations on the inner lan which may belong to diffent
subnets on the same physical lan.
 
If this to too esoteric for the HP3000-L, and I'll be the first to admit that this is
pushing the envelope, please contact me via e-mail.  If there is any interest I will
summarize and post the results.
 
I have, and have read, Craig Hunt's TCP/IP from ORA.  It is a good book but it dosen't
really answer the above questions.  As I have to reconfigure each and every interface
card on the network I would really like to know if this is going to work before I try
it out.
 
Regards,
--
James B. Byrne                  mailto:[log in to unmask]
Harte & Lyne Limited            http://www.harte-lyne.ca
Hamilton, Ontario               905-561-1241