Case Study

QualityCorp, Inc. is a small company with two sites (New York and Florida), each with LAN workstations, file servers, Voice over IP (VoIP), and Video over IP implementations. New York and Florida also have a connection to the Internet for external e-mail and World Wide Web (WWW) access. QualityCorp, Inc.'s network topology is illustrated in Figure 13-2.

Figure 13-2. QualityCorp, Inc.

QualityCorp, Inc. has dedicated IP lines to the NSP, and is using DiffServ to classify each traffic flow (the DiffServ code points are defined in IETF RFC 2474, which you can read at www.ietf.org/rfc/rfc2474.txt?number=2474), ensuring that each class of traffic is handled accordingly by the NSP. These code points are shown in Table 13-1.

Table 13-1. Code Points

Application Traffic	Code Point
Voice/Video	7
File Transfer/Sharing	4
Web Browsing	1

The NSP is carrying this DiffServ IP traffic over an ATM backbone, mapping the code points as shown in Table 13-2.

Table 13-2. Code Points Mapped to ATM CoS

Code Point	ATM CoS
7	CBR
4	VBRnrt
1	UBR