Priority Packet

1. Description
2. System Requirements
3. Installation
4. Configuration
5. Applicability and Limitations
6. Deployment Strategy
7. Terms Defined 


1. Description
===============

Priority Packet is a program that adds IEEE 802.1p tagging (also 
known as Traffic Class Expediting) and priority queue features to 
adapters. IEEE 802.1p tagging (see Terms Defined below) is a 
method of assigning different levels of priority to data packets based 
on user defined Priority Filters. This allows you to grant a greater 
share of available network bandwidth to critical applications.

To realize any gain from the IEEE 802.1p tagging feature, your 
interconnecting network hardware (hubs, switches, etc.) must also 
support IEEE 802.1p tagging. See Applicability and Limitations below for 
details. If you can't use IEEE 802.1p tagging, you can still use 
priority queuing to prioritize packets.

Priority queuing is a feature that creates a separate 
high priority queue in addition to the existing queue. Data packets are 
entered into these queues prior to being transmitted. The priority 
assigned to a packet determines which queue it goes into. Packets with a 
priority of 4-7 go into the high priority queue and are sent ahead of 
packets in the normal queue. This feature does not modify the packet 
contents and will work over legacy network equipment.

You can assign priorities based on network layer properties, such as the 
Node address of the destination computer, the Ethernet type, or by 
various properties of the TCP/IP and IPX protocol suites. See 
Configuration" below for details on setting up priority filters.

2. System Requirements
======================

This software program can be installed in Windows NT 4.0 or Windows 
98. It can also be installed in Windows 95 if it is service release 2 
(OSR2) or higher. If you are not sure which release of Windows 95 you 
are using, open Control Panel, double click System and check the release 
number on the General tab. If the release number is 4.00.950 or 
4.00.950A Priority Packet will not work. If it is 4.00.950B or higher 
you can install Priority Packet.

3. Installation
===============

To install, click Start, then Run. Enter the path to the Priority Packet 
setup program (Example: D:\PRTPKT\SETUP.EXE). Click on OK and follow the 
on-screen instructions to complete the install. A Priority Packet icon 
will be added to the Windows Control Panel.

Once Priority Packet is installed, the priority filters you create can 
always use priority queuing. However, packets are tagged only when the 
adapter has IEEE 802.1p/802.1q tagging enabled. To enable IEEE 
802.1p/802.1q tagging, double-click the PROSet icon in Control Panel. On 
the Advanced Settings tab, click on IEEE 802.1p/802.1q tagging and 
select Enabled. If there is more than one adapter in the system, this 
must be done separately for each adapter.

4. Configuration
================

To launch the Priority Packet program, open Control Panel and double
click the Priority Packet icon.

When you run the Priority Packet program, you will be given a choice of 
running locally or remotely. To run remotely, enter the IP address of 
the target remote computer. Priority Packet must be installed on the 
target remote computer.

Next you are presented with a dialog box with 2 tabs. One tab is titled 
Priority Filters, and the other is titled Statistics. The Priority 
Filters tab is where you can add, remove and examine the properties of 
the various priority filters you define. The Statistics tab is where you 
can examine the activity of your priority filters.

Adding a Priority Filter
------------------------

Click Add to start the Priority Filter Wizard. Two options are 
presented: Pre-Defined Priority Filter and Custom Priority Filter. 
Select Pre-Defined Priority Filter to select from a list of priority 
filters that have already been defined. Select Custom Priority Filter to 
define your own custom priority filter.

Using a Pre-defined Priority Filter
-----------------------------------

Pre-defined filters for many common applications are included with 
Priority Packet. These filters are all set for priority level seven and 
configured for the default ports. If you are not using the default ports 
or wish to assign a priority level other than seven, you will need to 
edit the pre-defined filter to customize it for your needs. See 
"Defining a Custom Priority Filter" below for configuration 
instructions.

Defining a Custom Priority Filter
---------------------------------

If you select Custom Priority Filter, you can choose from 3 basic types 
of priority filters;
* Node Address / EtherType Priority Filter
* TCP/IP Priority Filter
* IPX Priority Filter

A Node Address / EtherType Priority Filter assigns priority based on 
network "layer two" properties. These include the destination node 
address and the Ethernet packet type definition.

A TCP/IP Priority Filter assigns priority based on properties of the 
TCP/IP protocol suite. These properties include the TCP/IP address and 
subnet and specific protocols within the TCP/IP protocol suite.

An IPX Priority Filter assigns priority based on properties of the IPX 
protocol suite. These properties include the network number, destination 
node address and IPX socket.

Defining a Node Address / EtherType Priority Filter
---------------------------------------------------

If you select Node Address / EtherType Priority Filter, you have the 
choice of specifying a Destination Node Address. By specifying a node 
address for a priority filter, you limit the packet prioritization for 
that Priority Filter to a specific computer on the network. 

If you select Specify Node Address, you must enter the node address of 
the destination computer. When finished with this screen, click Next.

In the next step, you can specify an EtherType. If you specified a Node 
Address in the previous step but do not specify an EtherType, all 
traffic going to the specified node address will be given the priority 
you specify for this Priority Filter. You can select an EtherType from 
the list, specify your own EtherType or specify none. Click Next when 
you are finished.

In the next screen, enter the following information:
- Enter Priority Filter Name - Enter a unique priority filter name.
- Prioritization Method - Select "HPQ only" for Priority 
queuing only or "IEEE 802.1p and HPQ" for both tagging and 
Priority queuing. 
- Priority Level - Packets can be tagged with 8 possible levels of 
priority. 7 is the highest priority. Priority levels 0-3 will go into 
the normal priority queue, 4-7 will go into the high priority queue.

Click Next when you are finished. The next screen gives you a summary of 
your new priority filter's properties. Click Finish when you are done, 
then click Apply to activate the new priority filter.

Defining a TCP/IP Priority Filter
---------------------------------

If you select TCP/IP Priority Filter, you will be given the choice of 
specifying a Destination IP address and Destination Priority Filter 
Mask. If you skip this step, you must specify a protocol or port on the 
next screen.

If you specify a Destination IP address and Destination Priority Filter 
Mask, then this priority filter will affect only packets sent to that 
address (or address range as defined by the Priority Filter mask). If 
you enter a destination IP address and select Do Not Specify a Protocol 
on the next screen, then all IP traffic to that destination address will 
be sent with the specified priority.

Note: The "Destination Priority Filter Mask" is NOT a subnet mask. IP 
address bits will be ignored if they correspond to mask bits that are 
set to a logical "0". To limit the priority filter to one specific IP 
address only, the Priority Filter Mask must be set to 255.255.255.255. 
If you specify a mask other than 255.255.255.255, then all IP addresses 
falling within the range of the mask will be affected, including 
reserved, broadcast and network addresses. 

Example:

You enter an IP address of 123.123.123.20. The Priority Filter mask will 
affect the IP address range in the following way;

A Priority Filter mask of 255.255.255.255 will cause the Priority Filter 
to prioritize traffic to IP address 123.123.123.20 only.

A Priority Filter mask of 255.255.255.240 will prioritize all IP 
addresses from 123.123.123.16 through 123.123.123.31 

A Priority Filter mask of 255.255.255.0 will prioritize all IP addresses 
from 123.123.123.0 through 123.123.123.255.

The following Destination Priority Filter Masks are supported:
255.255.255.255
255.255.255.240
255.255.255.0
255.255.0.0
255.0.0.0
 
In the next screen, either select Do Not Specify a Protocol or Port, or 
enter the following information:

 - Specify Protocol (from list)
 or
 - Specify Protocol (other)

If you specify TCP or UDP as the protocol, you can enter a specific 
source port or all source ports, and a specific destination port or all 
destination ports.

In the next screen, enter the following information:

- Enter a unique priority filter name here: Enter Priority Filter name.
- Prioritization Method - Select "HPQ only" for Priority 
  queuing only or "IEEE 802.1p and HPQ" for both tagging and 
  Priority queuing. 
- Priority level - Packets can be tagged with 8 possible levels of
  priority. 7 is the highest priority. Priority levels 0-3 will go into
  the normal priority queue, 4-7 will go into the high priority queue.

Click Next when you are finished. The next screen gives you a summary of 
your new priority filter's properties. Click Finish when you are done, 
then click Apply to activate the new priority filter.

Defining an IPX Priority Filter
-------------------------------

If you select IPX Priority Filter, you have the choice of specifying a 
Destination Network number, Destination Host number or Destination 
Socket. You can assign any combination of these parameters, although at 
least one must be specified.

 - Destination Network Number
   This is the Net number assigned to a specific segment and frame type.

 - Destination Host Number
   This is the Node address of a specific LAN adapter

 - Destination Socket
   This is an IPX socket number. Only static IPX sockets can be entered.
 
In the next screen, enter the following information;

- Enter a unique priority filter name here: Enter Priority Filter name.
- Prioritization Method - Select "HPQ only" for Priority 
  queuing only or "IEEE 802.1p and HPQ" for both tagging and 
  Priority queuing. 
- Priority level - Packets can be tagged with 8 possible levels of 
  priority. 7 is the highest priority. Priority levels 0-3 will go into 
  the normal priority queue, 4-7 will go into the high priority queue.

Click Next when you are finished. The next screen gives you a summary of 
your new priority filter's properties. Click Finish when you are done, 
then click Apply to activate the new priority filter.

5. Applicability and Limitations
================================

IEEE 802.1p tagging (IEEE 802.1p) is a new IEEE standard for tagging, or 
adding additional bytes of information to, packets with different 
priority levels. Packets are tagged with 4 additional bytes, which 
increase the packet size and indicate a priority level. The addition of 
4 bytes to the packet increases the maximum Ethernet packet size from 
1514 bytes to 1518 bytes. This increase in maximum packet size imposes 
certain restrictions on the use of this technology. 

First, your interconnecting network infrastructure must support this 
standard or you will realize no gain from tagging. Furthermore, many LAN 
adapters, switches and routers that do not support 802.1p will reject 
any packets over 1514 bytes. Check with the hardware vendor if you are 
not sure if your network hardware will forward packets up to 1518 bytes 
in length.

Simple repeater type hubs (class I and II) will forward the tagged 
packets, but no gain will be realized from tagging.

802.1p compliant hardware must be configured to remove the additional 4 
bytes from the tagged packet before forwarding it to internetworking 
hardware or end nodes that will reject packets over 1514 bytes in length 
or do not support 802.1p tagging.

If your network infrastructure does not support 802.1p tagging, set IEEE 
802.1p/802.1q tagging to "Disable" (the default setting) in the adapter 
advanced properties. Priority queuing will still prioritize packets 
based on your priority filter settings.

In systems equipped with more than one supported adapter, each 
adapter must have IEEE 802.1p/802.1q tagging enabled separately. 

Priority filters apply to all adapters in a system and cannot be applied 
individually to adapters in multi-homed systems.

Tagging is currently not supported in conjunction with adapter teaming 
features (Adapter Fault Tolerance, Adaptive Load Balancing and 
Fast EtherChannel*). 

Both 802.1p packet tagging and high priority queuing are not compatible 
with network adapters based on the 82557 LAN controller chip.

6. Deployment Strategy
======================

No tools for automated installation are included with Priority Packet. 
Enterprise-wide deployment is best accomplished by utilizing a network 
management program, such as Intel(r) LANDesk(r) Management Suite.

7. Terms Defined
================

802.1p tagging
--------------
An IEEE standard for tagging, or adding additional bytes of information 
to, packets with different priority levels.

Destination Network Number
--------------------------
The IPX Net number assigned to a network segment. This number is unique 
for each segment and frame type combination. In NetWare* servers, this 
number is assigned when IPX is bound to an adapter using the syntax BIND 
IPX TO CARDNAME NET=#.

Destination Socket
------------------
The IPX protocol multiplexes functions by assigning a unique socket 
address to each function. There are very few static, or fixed, address 
sockets. Most socket addresses are assigned dynamically.

EtherType
---------
The EtherType value appears following the Destination Address field in a 
Version 2 Ethernet frame. The EtherType identifies the frame as 
belonging to one or another protocol family.

Layer Two
---------
The OSI networking model divides network functionality in to seven 
"layers". Layer one is the physical network hardware. Layer two is the 
data-link layer. This is the basic Ethernet layer, and includes the 
packet header. This header includes the source node address, the 
destination node address and the EtherType.

Network Layer
-------------
The OSI networking model divides network functionality in to seven 
"layers". Layer three is the Network layer. Network protocols such as 
IPX and IP operate at this level and make end-to-end connections 
possible.

Node Address
------------
A 12-digit identifier (a.k.a. MAC address or Ethernet ID) stored in the 
LAN interface adapter or, if locally administered addressing is being 
used, a local address assigned to the adapter. This number is unique for 
every adapter.

Packet
------
To be sent across a network, information must be broken up into packets of 
data. The Ethernet standard requires these packets to be no less than 64 
bytes long and no more than 1514 bytes long. The 802.1p tagging method 
alters this packet standard by adding 4 additional bytes of data, 
increasing the maximum packet size to 1518 bytes.

Priority Filter
---------------
A set of user defined parameters that specify possible attributes and 
desired priority setting of a data packet. The specified attributes are 
compared to each packet received by the driver and, if they match, the 
packet will be assigned the priority specified by that filter.

Source Port
Destination Port
----------------
The TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) 
protocols use numbered ports to differentiate services. A different port
number will be assigned to each service, one at the source and one at the
destination. There are many applications and services with "well-known" 
port numbers. Ports can also be assigned dynamically.
 
* Brand, name, or trademark owned by another company.

