 than in integration. The interworking protocols have to support the distribution along all planes (traffic plane and management plane) and layers (OSI-ISO layers) of the interconnected networks. In other words, they have to assure that the interconnection is held along all the layers com- posing the different networks, and that both traffic and management plane interconnection are included. The complexity is even greater when the two interconnected networks do not provide exactly the same services (mobile and fixed telephony, LAN and WAN, X25 and IP, PSTN and VoIP). In this case the gateways have to be able to handle the asymmetries in service as well. Why is my computer getting SO slow when downloading files from the Internet? The origin of the problem could be located either in the PC, the corresponding inter- working modems, the copper, cable modem or wireless access network, the ISP and finally in the different nodes on the Internet network. Its determination will not be a simple man- agement task, particularly considering that many operators are involved in the Internet communication and that they may have a null or at least very limited cooperation among their management systems. 1. The ITU-T (telecommunication network management - TMN) and the IETF (sim- ple network management protocol - SNMP) approaches on network management, although based on similar principles, finally became pretty different (different pro- tocols, different managed objects definitions, different terminology, etc.). Understanding Changing Telecommunications - Building a Successful Telecom Business 2. Usually isolated management systems already exist, either for particular layers, group of vendor's equipment or vendor's networks, or any combination of them. Some vendors' equipment and networks, particularly old legacy networks, use propri- etary management systems not based on the manager-agent principle. 4. Configuration management is frequently addressed by other means such as Telnet, proprietary CLI, FTP/FTAM for bulk transfer, and 