spirent testcenter how to configure a large scale ancp test · 3 proprietary and confidential there...

February 11, 2013

Spirent TestCenter

How to configure a large scale

ANCP test (w/out True Topology)

2 PROPRIETARY AND CONFIDENTIAL

There are different ways to configure Spirent TestCenter (STC) to test ANCP. We’ll go over the permutations.

What are the STC components involved in an ANCP configuration and how do they fit together.

A step-by-step example covering one of the ways we can configure a STC ANCP test (no True Topology and subs not sharing the AN’s VLAN).

Convert the (no True Topology and subs are not sharing the AN’s VLAN) to (no True Topology and subs are sharing the AN’s VLAN).

Notes/Caveats

Agenda


There are different ways to configure Spirent TestCenter (STC) to test ANCP.

With or without using True Topology (i.e., using "Incoming Links" and “Outgoing Links")

• this is a STC configuration option

AN and subscribers sharing AN's VLAN or not

• An example of sharing

AN creates adjacencies and send PORT UP/DOWN message on VLAN 10 but subscribers are on

stacked VLANs (outer,inner) = (10,1-1024)

• An example of not sharing

AN creates adjacencies and send PORT UP/DOWN message on VLAN 10 but subscribers are on

stacked VLANs (outer,inner) = (99,1-1024)

In this "How To" we will cover the case where we're:

• not using True Topology; and

• subscribers are not sharing the ANs' VLAN

We'll also see how to easily change the case where the subscribers are sharing the ANs' VLAN (and not using True Topology)

Different ways to configure an ANCP test


Access Node

Subscriber

• PPP - relay agent circuit/remote IDs

• DHCP - session IDs

Access loops

• "ties" ANs, Subscribers and line profiles together

Line profiles

• Associated with Access Loops

• Circuit-ID TLV

• Sub-TLVs

• DSL type

• Upstream data rate

• Downstream data rate

STC components involved in an ANCP

configuration and how do they fit together

Step-by-step example


1024 Access Nodes (AN)

Each AN has 10 PPP subscribers

Each set of 256 AN use a particular “line profile”

VLAN Schema

• ANs use VLAN 10

• Subs “behind” ANi use stacked

VLAN

(outer 99,inner i)

• That is the AN and subs are not

sharing VLANs.

The following steps will help guide you through building a scaled configuration to test this.

Example ANCP test topology

Spir

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Test

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First let’s create the device blocks that will represent the Access Nodes.

You do this the same way you would any other device block.

We need 1024 of these

1. Create the AN device blocks


Note that you can do this later but I prefer to do them here so they are available in a list to pick from.

Here we specify the sub-TLVs in the DSL Line Attributes sent in the Port Up and Port Down messages.

Since each group of 256 ANs will use a different line profile, we will create 4 line profiles.

2. Create the DSL line profiles


Now that we have our first and second ANCP components created, the ANs and Line Profiles, let’s now build the subscribers and associate them to their respective ANs using Access Loops.

We’ll do the next set of steps 4 times, each time configuring the subscribers behind a set of 256 ANs.

Use the “Access Loop Generator…” wizard to

create subscribers behind the ANs


3. Select Access Nodes Set “Loop blocks

per access node” to 1

Select 256 ANs

Note that you can multi-select by selecting the 1st AN, scrolling down to the 256th AN and <shift>+click

Then click on any of the checkboxes and all 256 will be selected.

Click “Next”


In this example the subscribers will be using PPP to obtain an IP address.

It is common that the subscribers include an identifier such as a Circuit-ID.

• If you need it you

can configure it

here.[1]

• You will see that in the ANCP “Line Profile” you can configure a Circuit-ID

TLV. These may need to match but unfortunately because ANCP and PPP

(or DHCP) are separate protocols, these are configured separately. [2]

4. Configure Subscriber Protocol


The “Access Loop Generator” wizard assumes that the subscribers will use stacked VLANs and so has a default “Number of VLAN Tags in Stack” of 2. This however will cause the creation of “True Topology” links which we didn’t want to use because the ANs and the subscribers are not sharing the ANs’ VLAN.

So set the topmost AN to “0” and use “Copy Down” to make them all “0”

5. Configure Subscribers

0


You can increase the “Subscriber Count” here to specify how many subscribers are behind each AN.

In this example we want 10 subscribers behind each AN.

NOTE: it’s important to do this here so that all the subscribers will be associated with a line profile and you can do them in bulk by using the “Copy down” feature. [3]

5. Configure Subscribers (cont’d)


6. Configure Access Loop TLVs

Here you can use a wildcard to help you match your RADIUS server’s Circuit-ID schema. [1] [2]

This TLV is sent in the Port Up/Down messages.


Here we assign the line profiles created in the second step to each host. For example the hosts behind Access Nodes 1 -256 use the “Line profile 1” line profile, Access Nodes 257 - 512 use the “Line profile 2” and so on.

Click on “Assign profiles to device ranges”

7. Select the line profile


This step creates the “Access Loop Blocks” which if you recall, tie the ANs, subscribers, and Line profiles together. So this is a key step.

If any of the profiles are selected, deselect them all.

Now select the line profile you want these subscribers to use and click “Finish”

7. Configure Line Profile (cont’d)


On “All Devices” select all the device blocks from all the pages.

Then click on “Edit Access Loops”

In this example we want to use the “Line profile 1” on the first 256 ANs and so on. So you can scroll through to see that you have the correct line profiles associated with the ANs. [4]

Repeat steps 3 through 7 for the remaining ANs

and subscribers and check your work


Back in step 5, we set “Number of VLAN Tags in Stack” to 0. This means that the subscribers currently have no VLANs and we need 2 so we’ll fix that here.

Find the “Encapsulation” column and on the topmost device block, click on the “…”

Change the “# of VLAN Headers” to 2 and click “OK”

Now this is IMPORTANT . Scroll over to the “Vlan #1 Modifier” column and notice it’s set to 1. We need to change that to “0”. So click on “…” [5]

And set the “Step” value to “0” and click “OK”. Do this for “Vlan #2 Modifier” as well.

8. Fix Subscriber’s VLANs (and MACs)


Now we’re going to copy down the encapsulation along with the VLAN modifiers.

Select all the subscriber device blocks. You can use the filter feature to filter the ANs out by creating a new filter where the Tags field equals “Host”

Once you have only the subscriber device blocks filtered, click in the upper left corner of the device grid and select “On all pages” (remember you have 1024 device blocks) and clikc “OK”.



Now we can use “Copy Down” to make all the subscribers device blocks have 2 VLANs.

There are 1024 device blocks so this may take a minute or two so please be patient.



Now we just need to configure the VLANs to match the VLAN schema we need. That was:

• Subs “behind” ANi use stacked VLAN (outer 99,inner i)

• Find “VLAN ID #1” column. This is the outer VLAN. Set the topmost device block’s to 99 and do

a “Copy Down” on all the filtered device blocks.

• Find “VLAN ID #2” column. This is the inner VLAN. Set the topmost device block’s to 1 and do

a “Fill Increment” on all the filtered device blocks.

Let’s do the same for the MAC addresses. Set the topmost device block’s “Source MAC Address” and do a “Fill Increment” on say the 5th octet to insure that none of the 10,240 subscribers will not have duplicate MACs.



1. Create the Access Node (AN) device blocks

2. Create the Line Profiles

3. For each set of ANs use the “Access Loop Generator”

1. Select the ANs you want to configure subscribers for

2. Configure the subscriber protocol

1. PPP or DHCP or none

2. Circuit-ID

3. Configure subscriers

1. Set VLAN stack to ‘0’

2. Set subscriber count to N

4. Configure Access Loop TLVs

1. Circuit-ID

5. Associate the Line Profile needed for this set of ANs/subscribers

4. Fix the subscriber VLANs and MACs

Step by step summary

Convert this configuration to

one where the subs are sharing

the AN’s VLAN


In this "How To" we will cover the cases where we're:

• not using True Topology; and

• subscribers are not sharing the ANs' VLAN

We easily change the case where the subscribers are sharing the ANs' VLAN by simply changing the outer VLAN on all the subscriber device blocks from “99” to the ANs’ VLAN, 10.

Just like in Step 8, we filter out all the subscriber device blocks, change the topmost device block’s “VLAN ID #1” to 10, select them all, and “Copy Down”.

Done!

Convert this configuration to one where the

subs are sharing the AN’s VLAN

Notes / Caveats


[1] Circuit-ID wildcard usage may be a challenge when scaling an ANCP test. Basically for each AN’s and PPP circuit-ID TLVs, the wildcards starting value will always default to 1 (or similar) and hence for each AN and PPP subscriber device block, you’d have to go and edit the start value. One recommendation is to use a wildcard that is unique for each AN as well as subscriber in the test, such as the MAC address wildcard. Of course this would mean that you’d have to adjust your RADIUS server to expect that circuit-ID naming schema.

Notes/Caveats


[2] ANCP and PPP (or DHCP) are separate protocols and so common attributes used in both protocols, in particular the Circuit-ID, need to be configured twice. Once in ANCP and once in the subscriber protocol, PPP or DHCP.

[3] If you miss this step, the additional subscribers will not have a line profile associated to them and so:

• There will be no Port UP/Down messages sent for those subscribers

• It will be tedious to go back and “map” a line profile to those subscribers (see “3” below).

Notes/Caveats


[4] If you “Edit Line Profiles…” and see multiple line profiles associated with an AN, you will have to go into each one and delete the unwanted ones. So that is why Step 7 is so important. Of course, you can always delete all the subscribers you created in Step 5 and start again.

[5] Because the VLAN modifier defaults to step=1, if we don’t set the topmost subscriber device block’s modifiers step=0, when we copy down, it will also copy down the modifier setting. As in the [4] above, if all else fails, just start again by set the topmost device block’s encapsulation to a VLAN depth of 0 and copy that down and start Step 8 again.

Notes/Caveats (cont’d)

Spirent Communications, Support Services

Thank You

spirent testcenter how to configure a large scale ancp test · 3 proprietary and confidential there...

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