By Tim Rooney, Director, Product Management, BT Diamond IP

The discipline of network management has long offered technical and business benefits to organizations with the centralization of the monitoring, control, and provisioning of distributed network elements such as routers and application or services databases. These benefits include holistic management of a network from a centralized point where appropriate resources can be leveraged for troubleshooting, resolution, and escalation. The centralized “top down” approach also lends itself well to supporting structured network change control procedures.

It’s a small leap to consider DNS and DHCP servers as network elements in need of network management within an IP network, as they provide critical enabling services to clients or subscribers. While not in-band or on the data path for user IP traffic like traditional network elements, DNS and DHCP servers provide foundational services required to make such in-band data paths possible and usable, including automated IP address assignment and simpler IP application navigation.

But one cannot manage DHCP pools and DNS information in a vacuum. This information must correlate directly with an overall IP address plan. An assigned DHCP address must be relevant to the subnet on which the connecting device is accessing the network. DNS information must correlate to the current IP addresses assigned to each device. The IP address management (IPAM) process enables an administrator to first carve up an IPv4 block like or 2001:db8::/48 into subblocks and subnets in an organized, logical manner. Assigning subnets outside of this hierarchical process can result in network inefficiencies and wasted IP address space.

For example, when allocating a new subnet, several factors must be considered: you need to identify address space that is available for assignment, that rolls up from a block aggregation perspective, that maps to address space set aside for the particular application in question (VoIP, wireless, etc.) and that has not been reserved by someone else for some purpose. Applying this logic using a spreadsheet is cumbersome, time-consuming and error-prone. And the impacts of a mistaken assignment can lead to network downtime.

The latest release of Cisco Network Registrar Prime IPAM not only simplifies this process but facilitates effective management of IP address space in accordance with business demands. A centralized database repository provides a consistent view of your entire IPv4 and IPv6 address space. Replication and redundancy features across our products help you achieve your business continuity objectives. Features such as reporting, auditing, discovery, reclaim, and administrator delegation are just a few of the additional product functions that help you save time and money. For more information, please check out this white paper: IP Address Management (IPAM) Best Practices.


Jamie Lerner

Senior Vice President and General Manager

Cloud and Systems Management Technology Group