QoS Gets A Little Better Definition

By SAROJA GIRISHANKAR

A series of emerging Internet standards promises to give Web businesses better control over the service they give to their best customers.

The Internet Engineering Task Force (IETF) working groups at their upcoming meeting in Minneapolis will push many proposed quality-of-service standards to fruition. A new working group was formed to define a standard for Web replication and caching.

The goal of the IETF standards is better quality of service in handling voice, video and data traffic during network bottlenecks and peak traffic. They will define how corporations can institute automated policies to prioritize access to their Web sites and will enable Internet service providers to offer comprehensive service level agreements across multiple ISP regions.

These standards also define a uniform way to manage Internet traffic from a central standards-based directory--LDAP--using multiple policy parameters, such as type of customer, traffic and time of day, across disparate vendor products, network devices and ISP territories.

"As a Web business, you will be able to decide which traffic coming into your site gets better quality of service and who gets preferential treatment," said Brian Carpenter, chair of the Internet Architecture Board and program director for Internet standards and technology at IBM. "Likewise, ISPs will be able to provide end-to-end [cross-ISP] classes of service based on traffic type and customer status."

The particular standards are the Differentiated Services (DiffServ), Common Open Policy Service (COPS), policy framework, and Web replication and caching. They have sprouted from a need to establish multivendor interoperability among proprietary policy-based networking efforts and an even more pressing requirement among businesses to simplify and automate their Web activities in the face of mounting traffic at their sites.

DiffServ is a prioritization scheme and a set of small building blocks from which 64 classes of service can be constructed.

COPS is a configuration protocol that lets a server pass on policy rules to a router, according to Carpenter.

Policy framework defines the architecture to build and manage interoperable policy-based networking systems using products that comply with DiffServ, COPS and other standards, such as LDAP, said John Strassner, co-chair of IETF's policy framework working group. A management information base for DiffServ also has been specified to let DiffServ products be managed by SNMP-based management systems.

The Web replication and caching standard, when formulated, will enable a common way for ISPs and businesses to cache and replicate data.

Corporate customers and ISPs were generally upbeat about the emerging IETF standards.

"We would like to have a way to prioritize access and service based on who the customer is and their standing with us," said Elizabeth VanStory, vice president of the online unit at OfficeDepot.com.

For MindSpring Enterprises Inc., an ISP, DiffServ will provide the company with the ability to prioritize different customers' megabit Internet services over cable and asymmetric digital subscriber line modems.

But for some ISPs, such as Uunet, DiffServ falls short.

"We wanted a simple solution to solve the simple problem of prioritization, but DiffServ is so feature-rich and so complicated that it raises the question of which vendor will support what, and how their products will interoperate," said Michael O'Dell, Uunet's chief scientist.

Regardless, vendors, including Cisco and IBM, already are far along in developing early versions of DiffServ and policy features across their products, which they expect to begin shipping before year's end.