Specifications

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Cisco CRS-1 Series Carrier Routing System XML API Guide

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Chapter 4 Cisco CRS-1 Series XML and Native Data Operations

Native Data Operation Content

Null Value Representations

The standard attribute “xsi:nil” is used with a value of “true” when a null value is specified for an

element in an XML request or response document.

The following example shows how to specify a null value for the element <HoldTime>:

</Timers>

</Neighbor>

Any element that can be set to “nil” in an XML instance has the attribute “nillable” set to “true” in the

XML schema definition for that element. For example:

<xsd:element name=”HoldTime” type=”xsd:unsignedInt” nillable=”true”/>

Any XML instance document that uses the nil mechanism must declare the “XML Schema for Instance

Documents” namespace, which contains the “xsi:nil” definition. Responses to native data operations

returned from the Cisco CRS-1 Series router declares the namespace in the operation tag. For example:

Operation Triggering

When structuring an XML request, the user should remember the following general rule regarding what

to specify in the XML for an operation to take place: As a client XML request is parsed by the

Cisco CRS-1 Series router, the specified operation takes place whenever a closing tag is encountered

after a series of one or more opening tags (but only when the closing tag is not the </Naming> tag).

The following example shows a request to get the BGP timer values for a particular BGP autonomous

system. In this example, the <Get> operation is triggered when the <GlobalTimers/> tag is encountered.

Sample XML Client Request to Trigger a <Get> Operation for BGP Timer Values

<?xml version="1.0" encoding="UTF-8"?>

<Get>

<AS>

</Naming>

</Global>

</AS>

</BGP>

</Configuration>

</Get>

</Request>

Sample XML Response from the Cisco CRS-1 Series Router

<?xml version="1.0" encoding="UTF-8"?>

<Get>