We covered the material in Sections 2.1 – 2.4 in Chapter 2. Topics include application-layer protocols, the Web and HTTP, email protocols, and DNS. (I also briefly discussed FTP but I wouldn't ask you questions about it. We didn't talk in much detail about email or DNS, but overview questions would still be appropriate.)
The exam will also cover sections 6.1 – 6.4 in Chapter 6. Key topics include the services offered by the link layer, error-detection, static and dynamic approaches to sharing channels, addresses and ARP.