Network Service Instance example

[david_legrand]

Hello CSDM gurus,

I love the new CSDM 5, the vision and renaming making things more understandable, specially with the Service Instance.

I think I understand that the new classes aren't much in use yet but could we have examples of them, specially the Network Service Instance?

I guess we should still have "Business Applications / Digital Products", one for Wired Ethernet, one for Wireless, we may have other types of networks, maybe a token ring remains somewhere and the EA needs to know if they should replace or maintain.

Then we have multiple Network Service Instances per Business Application, for example "Wifi Employee" secured by certificate and SSO authentication, one "Wifi Guest" and so on.

These Network Service Instances should be linked to all the hardware/software/appliances supporting them themselves being linked to technology management service offerings, most likely via Dynamic CI groups.

These Network Service Instances are linked to Business Service Offerings? such as "Guest Wifi HQ" with an higher commitment then "Guest Wifi small office". But shouldn't they also supporting Technology Service Offerings which will support other Service Instances?

What are your views on the matter? I know that mapping the network in the CMDB has always been a struggle.

[Mathew Hillyard]

Hi @david_legrand,

I believe that the Business Applications would be the specific apps rather than something more generic like "wired ethernet" - for example, (Cisco) AnyConnect or (Ivanti) SecureAccess would be the Business App, connected to the deployed Service Instances, themselves connected to the corresponding VPN Technology Management Service Offering in the example of one or more VPN services.

The infrastructure itself gets a little more complicated - as you mention, network mapping in the CMDB can be a struggle. For the CSDM I think you're right, typically one or more Dynamic CI Groups linked either directly to the Service Offering (if there is no software involved) or perhaps via a Service Instance - I guess it depends on the organisation's support model. Looking a bit more high level, in the portfolio I would expect to see a taxonomy layer for Network Services, then the individual wired, wireless, VPN etc. Services and finally Service offerings for each solution.

In terms of a relationship to the Service Consumption domain, typically the Technology Management Service Instance should be a child to the (business) service instances that rely on the technology, rather than connecting the Technology Management Service Instance directly to a Business Service Offering. I say "typically", because there will always be exceptions. Some customers insist that desktop support or end user computing be a business service offering but want it to be connected to the end user devices, which obviously exist in the Service Delivery domain.

I hope this helps!

Mat