packet tracer 5.3已经出来了，并已经有Linux版本。 新版本开始支持BGP。 Protocol Improvements Packet Tracer now models these protocols not included in earlier versions: FTP, SMTP, POP3,PPPoE, VoIP, and BGP. CCNA-related protocols and technologies include improved models of HTTP,DNS, DHCP, TCP, and IP. General Improvements * Supports Microsoft Window 7 and stopped support for Microsoft Windows 2000 * Supports current LTS version [...]