3Com (R) Corporation
EtherDisk (R) Diskette for the
3C90x EtherLink 10/100 PCI NIC Family
Fast IP Questions and Answers
Q: What is Fast IP?
A: Fast IP is an innovative software-based solution that provides an easy
and low-cost mechanism to improve performance on today's switched
networks. Fast IP allows end systems (desktops and servers) to
discover switched, Layer 2 communication paths. By creating switched
short-cuts, Fast IP allows end stations to bypass the router and
transfer data across wire-speed switched paths. Fast IP is part of
3Com's DynamicAccess software, an advanced network driver that brings
intelligence to the end systems to provide improved network performance
and control.
Q: What are the motivation & benefits of Fast IP?
A: Today's networks are evolving to an Intranet-based model, where network
managers are not able to predict traffic flows and where IP is
becoming the predominant network protocol. Most of the network platforms
in place today rely on general-purpose, CPU-based routers to provide
inter-subnet communication. With the exponential increase of network
users, faster connections, more demanding applications, and
omnidirectional traffic flow, those routers are becoming bottlenecks
that slow down the network and reduce users' productivity.
Fast IP delivers a mechanism to improve network performance by bypassing
those router bottlenecks. By allowing desktops and servers to
automatically find available switched paths to communicate at
wire-speeds, Fast IP delivers dramatic improvement over router's
performance. Still, Fast IP maintains the control of routing. Initial
Fast IP connection requests traverse the router on initiation, where
network managers can configure traffic policies.
Q: What is the performance gain when using Fast IP?
A: The fact that Fast IP bypasses the router in any communication provides
increased performance in switched networks even if there are just a
small number of network nodes using Fast IP. The performance gain
obtained when deploying Fast IP is directly related to traffic load on
the backbone router. The more traffic is pumped to it, the bigger the
latency and response time and the higher the performance gain. Internal
tests show performance increases in the order of 600% when routers are
loaded at 70 to 75%.
Q: How does Fast IP work?
A: Fast IP leverages the processing power of the end station. Based on data
to be forwarded to a separate subnet:
The end system will issue an NHRP request. The NHRP request is a
standard IP format packet with source and destination MAC and IP
addresses. Contained in the data portion of the packet is the source end
system's MAC address.
The NHRP packet is forwarded to a router in accordance with normal
intersubnet forwarding policies. The router retains its function as a
control point and filters or forwards the packet according to configured
policies.
The destination station, also running Fast IP, recognizes the NHRP
request and issues an NHRP response directly to the originating source
end system using the source MAC address received in the data portion of
the NHRP request.
When the NHRP reply is received by the originating source end system, it
will then redirect data packets directly to the destination end system
using its MAC address, rather than going through the router, resulting
in wire-speed switching.
The NHRP request-response process happens in parallel to data traffic
flow going through the router. Besides providing traffic control, this
process assures that data communication will not be interrupted while
the Fast IP short-cut is being established. If there is no switched path
available between end stations, traffic will continue flowing through
the router.
Q: What level of security is provided by Fast IP?
A: Fast IP relies on the router's configuration for security. Since the
first NHRP packet flows through the router, any restriction or filter
that has been configured on it will be applied. Communications that
were not allowed to happen before will not take place with Fast IP
since they follow the same routed path at initiation. Fast IP short-cuts
are initiated per IP session. Therefore, even in the case that two
different applications operate on the same server, there will be a Fast
IP request per application. If the source station is restricted to
either one, the router will not forward the request to that server and
the Fast IP short-cut will not succeed for that application, whereas the
other application's connection can be set up for a short-cut.
Q: How to position Fast IP and how does it contrast to Layer 3 Switching?
A: 3Com is a long-time leader in NICs and Layer 3 switching. Layer 3
Switches are designed to replace or displace the bottlenecked router,
moving it to the edge of the network for LAN/WAN use where forwarding
performance is less of an issue. Layer 3 switches are multiprotocol and
allow higher level of security, plus they also offer advanced features
like bandwidth allocation and, in conjunction with DynamicAccess
software, end-to-end LAN Traffic Prioritization (CoS). Fast IP is
designed to improve network performance in today's environments where
the router is a bottleneck, extending existing network investment.
The target customer for Fast IP are those networks that have a switched
infrastructure but rely on a traditional backbone router to provide
inter-subnet traffic communication. These customers want to improve
network performance but have budget limitations or are not ready to
displace the router. With Layer 3 switching and Fast IP, 3Com offers a
wide range of solutions to meet customers' needs.
Q: Is Fast IP a proprietary 3Com solution for 3Com NICs?
A: Fast IP is a solution based on the IETF NHRP (Next Hop Resolution
Protocol) draft. This ensures that Fast IP can work over existing
network devices (switches and routers), both 3Com and non-3Com. Fast IP
will also support the IEEE 802.1p/Q specification, providing a standard
solution to improve traffic forwarding over 802.1p enabled switches.
Q: When will Fast IP be available for other vendors NICs?
A: The first release of Fast IP is part of DynamicAccess software release
1.2 and it is focused on our current 3Com customers. Therefore, it works
on 3Com EtherLink NICs only. With DynamicAccess Software release 1.5 (1QCY98),
Fast IP will be available for other 3Com Ethernet cards as well as for
customers with non-3Com Ethernet NICs.
Q: When will Fast IP be available for UNIX systems (e.g., Sun, HP, IBM,
Silicon Graphics, etc.)?
A: We are currently in discussions with a number of UNIX systems vendors.
Announcement of their support for Fast IP will be made soon.
Q: Does Fast IP work over ATM?
A: Yes. Although we do not support short-cuts between ELANs today, Fast IP
will create short-cuts where multiple subnets are within the same ELAN.
The reason why Fast IP does not short-cut between ELANs is that in
sending the NHRP reply, it will be contained to the sender's ELAN. 3Com
is working on a software upgrade which will assist Fast IP in
short-cutting between ELANs. This software will be available in 1Q98 as
a free upgrade for the CB7000 family.
Q: When will Fast IP be available on ATM and FDDI NICs?
A: DynamicAccess software will be available for ATM and FDDI NICs at a
later release in 1998.
Q: What other protocols are supported by Fast IP?
A: The use of IP as the main protocol has increased over the last few years and
it is expected to be the dominant protocol in customer networks. Because
of the performance issues that this brings, Fast IP is targeted to solve
traffic problems for IP networks.
Q: What are the end system requirements for Fast IP?
A: Fast IP will be supported on desktops and servers running NDIS 3 network
drivers. Therefore Windows 95, Windows NT 3.51 and Windows NT 4.0 systems
will be able to support it. There are no special requirements for other
network devices such as routers or switches in order to support Fast IP.
There will be support for NDIS 3.0, 4.0 and 5.0, NetWare and UNIX drivers
in 1998.
Q: What are the network configuration requirements for Fast IP?
A: Fast IP is designed to bypass the router, particularly where the router
is a bottleneck, as well as to leverage the switched infrastructure. For
Fast IP to create short-cuts around routers, there must be a switched
path between source and destination.
Q: Do I need any hardware upgrades to support Fast IP?
A: No. Fast IP is software-based and can be implemented in any network,
regardless of the switching and routing infrastructure that is in place.
Q: What types of applications will benefit from Fast IP?
A: Fast IP will show dramatically improved performance for long-lasting
communication flows or for applications that make frequent use of a
intersubnet resource. Before issuing a short-cut request, Fast IP waits
for a short number of packets that are sent through the routed path,
eliminating unnecessary connection requests for short-lived flows such
as web-browsing. In addition, Fast IP periodically ages out unused
short-cuts. Therefore, the type of applications which will benefit from
Fast IP most are long-lasting traffic flows (for example files transfers,
server backups, document imaging, and so on). In addition, applications
that send out frequent periodic updates such as stock updates, manufacturing
equipment status updates, hospital equipment monitoring updates, and so
on will use Fast IP as long as the short-cut address is contained in the
address cache.
Q: How many short-cuts are maintained in cache memory?
A: The number of short-cuts per station is 256.
Q: How do we compare ICMP Redirect Message function to Fast IP?
A: ICMP (Internet Control Message Protocol, RFC 792) is an integral
part of IP. ICMP is necessary for reporting errors occurred when
processing IP datagrams. ICMP messages are several and provide
information to solve datagram delivery problems. Among those messages,
the Redirect Message has been mistakenly compared to Fast IP as an
existing IP mechanism to provide short-cuts in router-based networks.
The ICMP Redirect Message is used when more than one router is attached
to a LAN. End stations typically have only one default router. The
default router (also called a default gateway) is used when sending
packets to destinations that are not on the end station's local LAN. The
end station sends all non-local traffic to its default router, which
then forwards it to its destination. If this router can tell (by
information learned from its routing protocols) that another router on
this LAN is closer to the destination, it uses the ICMP Redirect message
to tell the end-station that when talking to this destination it should
use a different egress router.
Fast IP provides a mechanism to discover switched paths across corporate
networks to provide improved performance (by minimizing router hops).
ICMP Redirects only optimize the exit path for traffic from an
end-station to a non-local destination, but all the non-local traffic
must still cross at least one router, even if there is a layer 2
switched path available.
Q: Will I see an increase in CPU utilization with Fast IP?
A: In a Fast IP-enabled network, you will see an increase in CPU utilization
at the client when you enable Fast IP. This is because of the increased
throughput on the wire that is achieved with Fast IP. If your system has
limited CPU resources, you may want to leave Fast IP disabled.
(%VER FASTIP.TXT - Fast IP FAQ v1.0b)
Download Driver Pack
After your driver has been downloaded, follow these simple steps to install it.
Expand the archive file (if the download file is in zip or rar format).
If the expanded file has an .exe extension, double click it and follow the installation instructions.
Otherwise, open Device Manager by right-clicking the Start menu and selecting Device Manager.
Find the device and model you want to update in the device list.
Double-click on it to open the Properties dialog box.
From the Properties dialog box, select the Driver tab.
Click the Update Driver button, then follow the instructions.
Very important: You must reboot your system to ensure that any driver updates have taken effect.
For more help, visit our Driver Support section for step-by-step videos on how to install drivers for every file type.