Designing Enterprise Edge Connectivity © 2004 Cisco Systems, Inc. All rights reserved. Designing the Internet Connectivity Module ARCH v2.13-1

© 2004 Cisco Systems, Inc. All rights reserved. ARCH v Enterprise Needs for the Internet Key Requirements From Company Site to Internet Functionality Performance Scalability Availability Manageability Cost effectiveness From Internet to Company Site Functionality Performance Scalability Availability Manageability Security Cost-effectiveness

© 2004 Cisco Systems, Inc. All rights reserved. ARCH v Internet Connectivity Module

© 2004 Cisco Systems, Inc. All rights reserved. ARCH v Network Address Translation Public addressing Less security No need for address translation Requires one address for every destination Private addressing More secure Requires address translation Allows one public address for multiple destinations

© 2004 Cisco Systems, Inc. All rights reserved. ARCH v Single ISP Connectivity

© 2004 Cisco Systems, Inc. All rights reserved. ARCH v Multi-Homed Enterprise

© 2004 Cisco Systems, Inc. All rights reserved. ARCH v Routing Protocol and IP Addressing Design Considerations Routing protocol considerations –Are static routes most appropriate? –Does the service provider use BGP? –What areas or networks are required for the Internet connection? IP addressing considerations –Are private, public, or both address types required? –How many end systems need access to the public network only? –How many end systems need to be visible to the public network also? –How and where will you cross the boundaries between the private and public addresses?

© 2004 Cisco Systems, Inc. All rights reserved. ARCH v Example: Internet Connectivity

© 2004 Cisco Systems, Inc. All rights reserved. ARCH v Summary Enterprises frequently require access from the internal network to the Internet, and may provide access to public servers for outside users over the Internet. NAT is designed to simplify and conserve IP addresses, as it enables private IP internetworks that use nonregistered IP addresses to connect to the Internet. There are two methods to connect to an ISP: a single-run and multi-homed method. The simplest method is to provision a single connection to the ISP. To support redundancy and load sharing, use multi-homing. An Internet connectivity example provides guidelines to help you design your own solution.

© 2004 Cisco Systems, Inc. All rights reserved. ARCH v Learning Activities Case Study: OCSIC Bottling Company –Design the site-to-site WAN for the OCSIC Bottling Company –Design a remote-access edge solution for the OCSIC Bottling Company –Design the Internet Connectivity module for the OCSIC Bottling Company –Provide justification for each design decision OPNET IT Guru Simulation –View the instructor demonstration and consider the key design questions