- Page 1: iDirect enabled technology: Introduction
- Page 2: TCP over satellite and reliability
- Page 3: Rain fade and performance issues
- Page 4: Services
The amount of upstream and downstream bandwidth for each individual site is controlled and managed using rate limiting. In this way, a business pays only for the amount of bandwidth they require on a per site basis. A site can use all the bandwidth available up to the point that it is rate limited.
Committed Information Rate (CIR)
As indicated above, each iDirect remote VSAT satellite router is assigned a small amount of dedicated bandwidth, eliminating the need to contend for an opportunity to transmit, and guaranteeing that no matter how busy the network, at least that basic amount of bandwidth will always be available. Additional CIR bandwidth can be permanently dedicated or dynamically allocated on a per site basis to support specific requirements for an additional cost. Dedicated CIR is bandwidth time slots permanently assigned to specific remotes that cannot be used by any other VSAT. Dynamic CIR is allocated to specific sites when they have data to send, otherwise the bandwidth time slots are put back in the shared pool for general use among all VSATs. A key differentiator is the speed with which dynamic CIR can be assigned. Most systems that provide a CIR capability will take 10’s of seconds to establish the dedicated bandwidth capacity, while the iDirect system will make it available in sub-second time.
Many companies desire the use of satellite broadband for private IP networking instead of, or in addition to Internet access. This is easily accomplished. Traffic from remote sites lands at the teleport, where Internet traffic is directed to a firewall and dropped with no intermediate hops onto a Tier One ISP backbone at very high speeds. Private IP traffic is directed to a Frame Relay, T-1, VPN or other wireline link that terminates back at the company’s headquarters location. The connection is private in all regards, similar to a Frame Relay network. For additional security, most iDirect-enabled Network Operators support iDirect’s optional 3DES encrypted service across the satellite link. Everything to and from the remote VSAT is encrypted across the satellite link. The benefits of TCP and web acceleration are maintained. The customer can decide whether to encrypt links to some or all of their remote offices. The 3DES encryption is provided by the Hifn chipset that is found in VPN appliances and routers from many vendors. The performance hit for 3DES encryption is less than 1%.
Some organizations have specific requirements for security, and satellite latency can create some interesting challenges for VPNs. We understand these limitations and can provide consulting and advice for a range of security solutions that work over satellite such as:
- SSL-based VPNs that are easy to deploy because no client software is required. They ride on top of TCP, so TCP Acceleration continues to operate.
- SLE (Selective Layer Encryption) solutions that encrypt data but leave the TCP control information alone so that TCP Acceleration can work properly.
- Encapsulation techniques that wrap an IPSec VPN packet in a new TCP header that can be accelerated.
Many satellite systems require that you convert a PC into a router in order to share the connection. Others provide a dedicated PC or device that delivers a proxy service to share the connection with multiple users. The iDirect solution uses a small hardware box with no moving parts, that includes standard routing features such as Static IP, RIP2, IGMPv2, DHCP, NAT, DNS caching, VLAN tagging, GRE Tunnel Acceleration, etc. It delivers a ‘hot’ 10/100 Ethernet port to connect to your networking gear. The satellite modem, router, TCP acceleration, and QoS engine are all in a single, reliable, integrated package.
Service delivery options
Most legacy systems require that the service provider procure a large chunk of space segment, typically an entire transponder. This means that they must design their service offering for a mass market, with an eye to servicing and supporting as many subscribers as possible on a network. The iDirect solution supports the ability to economically engineer smaller, customized service offerings to meet specific customer demands. There are generally three types of service offerings available that we shall refer to as Enterprise, Carrier/Premium, and Private Network. Not network operators offer all three service types. Due to the flexibility of the iDirect solution for a network operator to engineer a service offering to specifically address specific markets, there is variance in the offerings from different providers. Business Satellite Solutions will work with you to determine which service offering is best for your requirements.
With this solution, a service provider will generally configure a service that provides an a la carte’ menu of bandwidth offerings. This is similar to typical business broadband solutions like DSL and Fixed Wireless that are shared by multiple companies at reasonably conservative sharing or subscription ratios. Typical generic service offerings range from 128 Kbps x 64 Kbps up to 4 Mbps x 512 Kbps. This is a good solution for the enterprise with just a few remote sites. Bandwidth levels can be upgraded on a per site basis as requirements increase.
Carrier or premium services
These services are generally intended to be used for Internet Cafe’s, ISP backhaul service or very high volume business use. They are also appropriate for solutions that have a high volume of concurrent VoIP or Video/IP transmissions. Generally some percentage of the service offering has a built in CIR to ensure sufficient dedicated bandwidth to meet the saturated data throughput requirements for these heavy use’ applications. Additional CIR may be available for additional cost to meet the specific requirements of the situation.
Private network service
An enterprise that has many remote sites may opt to procure a private network service in which bandwidth is shared only by that company’s remote sites. The service can be customized and designed with sharing ratios to meet specific business requirements. A business may opt to increase the sharing or subscription ratio in order to reduce the cost per site. They may opt to select bandwidth rates that are higher than a generic service offering and install the appropriate dish and transmission equipment to support the higher rates. The iDirect solution supports up to a maximum of 9Mbps x 4 Mbps. Companies with many sites across multiple time zones may distribute them across multiple carriers in order to split the traffic load by time of day. Business Satellite Solutions uses an iDirect-provided segment analysis tool to help determine the correct sharing, CIR and other parameters to meet the specific business requirement.
In addition to fixed installations, the iDirect solution is excellent for mobile or transportable satellite solutions that can be assembled and commissioned in a matter of a couple hours, then packed up and moved to a new site as needed. With this solution, a company might arrive on site, set up and point the dish; use a GPS to enter the location coordinates for the dish and bring the system online quickly. With a couple of VoIP phones and a small switch or hub, a remote site can have extensions off the corporate PBX, and be connected to the Internet and/or headquarters in no time.