Legal

Introduction and Background

Current public IP address allocations are issued from the American Registry for Internet Numbers (ARIN) under the authority of the Internet Assigned Numbers Authority (IANA). Cbeyond supports ARIN and their policies, which are in turn in line with IANA.

As a responsible member of the Internet working community, CBEYOND must abide by the policies set forth by ARIN in regard to IP address allocation to customers. The public IP address space that is currently unassigned in IPv4 space (32-bit IP addressing) is becoming constricted, and measures to ensure the future viability of the Internet may cause conflicts with customer network planning, unless responsible and efficient usage of subnet space is agreed upon between ISPs and their customer base. In cooperation with our customers, CBEYOND must plan to make the most efficient use of the allocated network space so that CBEYOND can continue to route traffic and obtain new network address space when it is requested. CBEYOND encourages and supports customers in the growth of their networks, and CBEYOND will assign addresses to customers who genuinely require the address space for their networks. However, CBEYOND must examine all requests for address space with care to validate the use of the IP addresses that are allocated. CBEYOND will request customers to re-design their networks before allocating new address space to them if CBEYOND feels that the current range of addresses is sufficient for customer requirements.

IP Address Assignment

Customers will be assigned public or private IP addresses according to their need for such addresses. Your technical support advisor (TSA) will ask you various questions to help determine how many IP addresses that you need immediately and over the next 12 months. Relevant questions may include some of the following:

• How many subnets?
• How many servers?
• How many printers?
• How many desktop/workstations?

Default IAD Configuration For Customers

Whenever possible, CBEYOND will implement Network Address Translation (NAT) on the customer IAD. Cbeyond can also provide an IAD-based Dynamic Host Configuration Protocol (DHCP) server to assist in address management. This will provide adequate security and connectivity for most customer LANs.1 CBEYOND can utilize existing customer private networks or provide IP addressing for use as needed.

Internet-accessible Services and Port Forwarding

For customers with Internet-accessible services, Cbeyond will forward ports for the following standard network services:

• HTTP (port 80)
• HTTPS (port 443)
• FTP (port 21)
• SSH (port 22)
• Telnet (port 23)
• SMTP (port 25)
• POP2 and POP3 (ports 109 and 110)
• IMAP (ports 143, 220, and/or 993)
• PPTP-based VPN (port 1723)
• PC Anywhere (various ports)

Cbeyond can forward an individual protocol, across one port, to one internal IP address. For example, Cbeyond can forward port 80 - usually supporting HTTP services - to one IP address. So, it cannot be used as a load balancing service. For customer networks with port forwarding requirements beyond those listed above, Cbeyond may design other IAD configuration and/or IP numbering solutions.

Public IP Addresses

CBEYOND will assign public IP addresses according to Classless Inter-Domain Routing (CIDR) or classless boundaries (i.e., 2, 4, 8, 16, or 32 IP addresses). For requests above 16 IP addresses (i.e., a /28), you will be asked to provide justification for such requests. Such requests may include network diagrams, network plans, network topologies, and planned network expansion. Based upon your justification, CBEYOND may provide you with the requested public addresses, or ask you to more efficiently utilize your current address space. This applies both to new customers as well as existing customers.

You may reference Request for Comments (RFC) 2050 for more details on this subject.

New Customers

Upon order confirmation, a CBEYOND TSA will work with you to obtain answers to the following questions:

1. Will you be using Network Address Translation (NAT) through Cbeyond's IAD?
   If you will use NAT through Cbeyond's IAD, then you will need to number your LAN, based on requirements for an RFC-specified private network. Cbeyond can provide you with a compliant /24 subnet of private IPs, to number your network. Alteratively, you may number your network with any compliant range of private IP addresses.
2. Will you be using Dynamic Host Configuration Protocol (DHCP) through Cbeyond's IAD? Will you need static IP addresses on any LAN devices (for port forwarding or other reasons)?
   If you will use DHCP through Cbeyond's IAD, Cbeyond will load a compliant /24 subnet of private IP addresses into the DHCP server. These IP addresses will be dynamically served to LAN-connected devices. Cbeyond will need to identify any static IP addresses used on your LAN (for port forwarding or otherwise). Cbeyond will exclude these static IP addresses from the address range loaded into the DHCP server. If you will not use IAD-based DHCP, Cbeyond can remove this service from the IAD configuration.
3. Will you be using a proxy firewall?
   Although NAT implemented through Cbeyond's IAD provides an inherent level of network security, some customers will implement proxy firewalls for an enhanced level of LAN security. If you are implementing a firewall, this will impact the design of Cbeyond's IAD configuration. For most firewall installations, Cbeyond will route all IP packets through to the LAN (no NAT) and provide a subnet of public IP addresses to the customer.
4. Do you have an existing net block (public IP addresses) from another ISP?
   Customers who have existing IP address blocks with a previous ISP will be required to re-number within the CBEYOND CIDR blocks. Per the guidelines of ARIN, IP addresses from other ISPs are non-portable. Therefore, address space that has been previously allocated by another ISP must be returned to that ISP when switching providers. CBEYOND will not route non-portable IP addresses.
5. Do you have an existing net block (public IP addresses) directly from ARIN?
   Due to limitations on the size of the global routing tables, many large ISPs will not route portable blocks which are smaller than a /19 (or 32 Class C's). For this reason, CBEYOND encourages customers with such space to migrate off of those blocks and return them to ARIN. Under some circumstances, it may be possible for these blocks to be routed. However, there may be permanent or intermittent difficulties with some parties on the Internet in reaching your network(s). Cbeyond will work with you either to advertise your address space across the Internet or to provide a replacement IP address allocation from within CBEYOND CIDR blocks.
6. How many Internet-accessible hosts do you have today? in the next 12 months? Can these hosts be supported by forwarding ports through NAT?
   It is in the best interest of Cbeyond and its customers to implement port forwarding in the IAD, whenever possible. If customer applications can be supported through forwarded ports in the IAD, Cbeyond will forward ports to private IP addresses, which should be installed on Internet-accessible hosts. If port forwarding cannot support the requirements, then Cbeyond may initially provide up to a /28 subnet of public IP addresses (16 IP addresses), allocated through Cbeyond's CIDR blocks. If public IP addresses are allocated, Cbeyond will verify that customers understand the risks of exposing their LAN devices to the public Internet.¹
7. Do you need more than a /28 subnet (16 IP addresses) of public IP addresses?
   Cbeyond will ask for justification and more detailed information to provide over 16 public IP addresses. Any special considerations for network address assignment should be accompanied by a network map that includes the number of hosts and their placement relative to Cbeyond's IAD. All subnetting should be clearly shown. CBEYOND will assign the appropriate size CIDR block to the customer based on this map. In making the assignment, CBEYOND may suggest alternate means of network design to conserve address space.

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