I am developing a print server and want...
Articles and Tips: qna
01 Aug 2001
Q.
I am developing a print server and want them to be able to connect to NetWare 5.x servers. I already have NDS-NCP protocol over IPX in my products, and I have already developed print servers that implement NDS connectivity using NCP (NEST) over IPX. However, I am not sure what I have to do to implement Pure IP connectivity in my products.
I think the basic protocol of NCP over Pure IP is the same as NCP over IPX, with a few differences. If this is correct, the print server should work as follows:
Print Server logs in to NDS tree for print server with NCP and NEST over IP.
Print Server retrieves print jobs from a queue in the NDS tree and can print the print jobs.
If this is correct thinking, there must be is a difference between using NCPs with Pure IP and NCPs over IPX, when using the Keep-Alive control. In the case of IPX, the Keep-Alive packet is sent to Print Server's socket 0x1001 from the connected File Server in the table below:
|
|
File Server
|
Print Server
|
|
network address
|
0x12345678 |
0x00000001 |
|
node address
|
0x000000000001 |
0x008092012345 |
|
socket
|
0x0451(NDS socket) |
0x1000 |
In the example, the NCP command is exchanged between the File Server's socket 0x045c and Print Server's socket 0x1000. The NCP Keep-Alive packet is exchanged between File Server's socket 0x045c and Print Server's socket 0x1001(=0x1000+1).
But in the case of NCP over Pure IP (TCP and UDP), what kind of protocol is used for the Keep-Alive functionality?
A.
Rather than try to implement queues, you might consider the following information from the NEST support forum:
"We are looking for Native TCP/IP support--or another way to say it, TCP/IP support for NetWare 5.x that supports printing via the queue system (NCP calls over TCP/IP instead of IPX).
"Novell does not plan, nor is it encouraging development of, TCP/IP support for the queue-based printing system. We are moving away from that toward NDPS which is an NDS-based system.We strongly recommend that you develop an NDPS gateway for IP support using your LPR and LPD on your current system.
"NetWare 5.x supports three printing systems: NDPS, Unix, and queue-based. NDPS is the default choice when setting up the system. If you have LPR/LPD in your current print server, you can use Novell's NDPS gateway that ships with NDPS to communicate to your print server over IP.
By the end of this year we will have an embedded NDPS Printer Agent kit available that will support IP. Our suggestion is to encourage your users to use NDPS rather than the older queue-based system."
* Originally published in Novell AppNotes
Disclaimer
The origin of this information may be internal or external to Novell. While Novell makes all reasonable efforts to verify this information, Novell does not make explicit or implied claims to its validity.