IPAM

Internet Protocol Address Management is a means of planning, tracking, and managing the Internet Protocol address space used in a network. Most commonly, tools such as DNS and DHCP are used in tandem to perform this task, though true IPAM will glue these services together so that each is aware of changes in the other (for instance DNS knowing of the IP address taken by a client via DHCP, and updating itself accordingly). Additional functionality, such as controlling reservations in DHCP as well as other data aggregation and reporting capability, is also common. IPAM tools are increasingly important as new IPv6 networks are deployed with larger address pools, different subnetting techniques, and more complex 128-bit hexadecimal numbers which are not as easily human-readable as IPv4 addresses. IPv6 networking, mobile computing, and multihoming require more dynamic address management and are causing technical obsolescence of the early generations of IP address management software and spreadsheets used for address management.

Third-Generation concept

The latest concept in IP Address Management, referred to by many vendors as "Third Generation", is that many network service configurations (such as DNS and DHCP) can be automated based a shared network-describing data-source. Comparing configuration files between switches, DHCP servers, DNS servers, and IP space tracking spreadsheets would show a large amount of overlap in information. Third Generation IP Address Management looks at creating an abstracted database to store all information about a network and use service specific abstraction layers to extract information and automatically configure those network services.

In theory, third generation IP address management removes the chance that human error may lead to conflicting information across configuration files and spreadsheets used to track IP space allocation.

Future expansion of this concept could possibly see partial automation of devices such as switches and routers.

Solutions

There are three different models of IPAM solutions that all of the different products fit into.

oftware model

This is the oldest model, which consists of a database to store all of the information, an interface to manipulate it, and a system to take that information and distribute it to currently deployed stand-alone DNS and DHCP servers. The software model manages other DNS and DHCP servers, but those servers are not part of this model and need to be purchased from another source. The advantage of this solution is that existing infrastructure does not need to be replaced, and access into the database is simpler for outside scripts. The pricing model is the total of the software cost, yearly maintenance and number of hosts.

Appliance model

The appliance model is a one-shop solution where the database, DNS and DHCP servers are all supplied as simple to manage appliances which are easily maintained. This solution is normally much easier to support with a higher ROI, but it involves a forklift upgrade (your current infrastructure is replaced with the new appliances). The pricing model is normally simpler; the cost of the appliance + yearly maintenance, and not including a per IP fee.

Hybrid model

The hybrid model uses appliances where there is less chance of having to maintain an existing platform. For example, most organizations do not currently have an IP Address Management server so there is no server to maintain or upgrade with new software. However, software can be installed on existing DNS or DHCP servers to allow them to be controlled by the management appliance. These software controlled servers could also be mixed with appliances.

Hosted model

The database and external DNS services are hosted at a vendor's datacenter with web-based interfaces for clients. Internal DNS and DHCP services are provided by appliance units that are owned and maintained by the vendor, and hosted internally within the company. This solution is by far the easiest to maintain, as all equipment support is the responsibility of the vendor, and the client only adds and removes database information. The downsides of this solution are that it is a fork lift upgrade, and the solutions are new, lacking many options available in the other models. The pricing model for the hosted solutions is based on the number of external IP’s (or number of queries per month) and the monthly cost for each internal node pair.

More information can be found via the independent www.ipam.nl site