October 7, 2016 | Written by: John Ty McCarthy
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Companies are striving to implement more cost-effective IT environments using hybrid clouds that include both on-premises and off-premises resources. Direct Link on IBM SoftLayer, introduced in my previous blog post, helps IBM Cloud clients integrate their private, public and hybrid clouds with high performance, security-rich connections.
Here’s how Direct Link connects your IT resources.
Physical connectivity occurs through a dedicated fiber connection (one or 10 Gigabits per second) that links a customer’s service equipment and the network equipment in an IBM point of presence (PoP). The method of connection depends on the type of connection:
- Direct Link NSP: Customers directly connecting their existing data centers to the IBM Cloud would terminate a telco-provided Ethernet, MPLS, DWDM or SONET connection into their service endpoint equipment within an IBM PoP, then run a fiber cross-connect from that equipment to the IBM patch panel. The panel connects to ports on the IBM cross-connect router (XCR) in the PoP, which routes traffic to an IBM data center and ultimately through IBM’s carrier-grade, private global IP network to its final destination. Customers are responsible for purchasing the physical fiber cross-connect.
- Direct Link colocation: Customers with colocation facilities within the same building or campus as an existing IBM data center would terminate a redundant fiber connection into a cross-connect panel installed in the POD (server farm) where their compute resources are provisioned. Customers are responsible for purchasing the fiber cross connect from their colocated facility to the IBM data center patch panel, which can span different floors in the same building or different buildings.
- Direct Link cloud exchange: Customers using an IBM-approved cloud exchange partner would terminate a telco WAN service into an IBM PoP (same as Direct Link NSP) and also into the cloud exchange partner’s software-defined network, creating secure point-to-multipoint virtual connections among their private networks, the cloud exchange and the IBM Cloud.
(See the Direct Link FAQ for more information.)
Network connectivity is defined by routing policies for an organization’s IP address space. Public IP addresses are universally assigned and may be static (reserved for a particular network resource, such as a server) or dynamic (they change as resource demands change but come from an assigned public pool). Private IP addresses are used for internal traffic shielded from the public internet by network elements such as routers or firewalls. This makes it possible for the same IP address space to be used by multiple parties simultaneously without conflict.
IBM Direct Link has three network connectivity options:
- Dual IP remote hosts: Customers add additional IP addresses (or reassign the IP addresses for existing on-premises, colocated or cloud exchange hosts) to include public IP address space assigned to the IBM Cloud. This allows IBM to securely route customer traffic between the customer’s private network and the IBM network.
- Network address translation (NAT): Customers configure NAT on network elements acting as private network gateways (usually a router or firewall). This allows assigned public IP address space to be used on private networks without conflict, since public IPs are converted to private IPs (and vice versa) as they cross the NAT gateway. For customers with private IPs that conflict with IBM IPs, NAT can be provisioned in both directions (source and destination).
- Bring-your-own IP (BYOIP): Customers bring their assigned public IP address space into the IBM private network. Customers must create generic routing encapsulation (GRE) or IP security (IPSec) tunnels between their on-premises or colocation network and the IBM network. They can then use any IP address space they choose on the private network, as long as there are no conflicts with IBM’s public or private address space, and then route traffic across the tunnel between networks.
These methods of connectivity contribute to providing the security and performance that hybrid clouds require in enterprise-scale IT environments.
To learn more about Direct Link and other features and technology available with IBM SoftLayer, check out our Cloud How-To webcast series.