draft-ietf-manet-zone-iarp-00.txt   draft-ietf-manet-zone-iarp-01.txt 
INTERNET-DRAFT Zygmunt J. Haas, Cornell University INTERNET-DRAFT Zygmunt J. Haas, Cornell University
Marc R. Pearlman, Cornell University Marc R. Pearlman, Cornell University
Prince Samar, Cornell University Prince Samar, Cornell University
Expires in six months on July 2001 January 2001 Expires in six months on December 2001 June 2001
The Intrazone Routing Protocol (IARP) for Ad Hoc Networks The Intrazone Routing Protocol (IARP) for Ad Hoc Networks
<draft-ietf-manet-zone-iarp-00.txt> <draft-ietf-manet-zone-iarp-01.txt>
Status of this Memo Status of this Memo
This document is an Internet-Draft and is NOT offered in accordance This document is an Internet-Draft and is in full conformance with
with Section 10 of RFC2026, and the author does not provide the IETF all provisions of Section 10 of RFC 2026, except the right to
with any rights other than to publish as an Internet-Draft. produce derivative works is not granted.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-Drafts. other groups may also distribute working documents as Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference material time. It is inappropriate to use Internet-Drafts as reference material
or to cite them other than as "work in progress." or to cite them other than as "work in progress."
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zones can be used to efficiently guide route queries outwards (via zones can be used to efficiently guide route queries outwards (via
bordercasting) rather than blindly relaying queries from neighbor bordercasting) rather than blindly relaying queries from neighbor
to neighbor. The proactive maintenance of routing zones also helps to neighbor. The proactive maintenance of routing zones also helps
improve the quality of discovered routes, by making them more robust improve the quality of discovered routes, by making them more robust
to changes in network topology. Once routes have been discovered, to changes in network topology. Once routes have been discovered,
IARP's routing zone offers enhanced, real-time, route maintenance. IARP's routing zone offers enhanced, real-time, route maintenance.
Link failures can be bypassed by multiple hop paths within the Link failures can be bypassed by multiple hop paths within the
routing zone. Similarly, suboptimal route segments can be identified routing zone. Similarly, suboptimal route segments can be identified
and traffic re-routed along shorter paths. and traffic re-routed along shorter paths.
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Contents Contents
Status of this Memo . . . . . . . . . . . . . . . . . . . . . . i Status of this Memo . . . . . . . . . . . . . . . . . . . . . . i
Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . i Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . i
Applicability Statement . . . . . . . . . . . . . . . . . . . iii Applicability Statement . . . . . . . . . . . . . . . . . . . iii
A. Networking Context . . . . . . . . . . . . . . . . . iii A. Networking Context . . . . . . . . . . . . . . . . . iii
B. Protocol Characteristics and Mechanisms . . . . . . . iii B. Protocol Characteristics and Mechanisms . . . . . . . iii
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . 1 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . 1
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B. Data Structures . . . . . . . . . . . . . . . . . . . . 5 B. Data Structures . . . . . . . . . . . . . . . . . . . . 5
C. Interfaces . . . . . . . . . . . . . . . . . . . . . . . 6 C. Interfaces . . . . . . . . . . . . . . . . . . . . . . . 6
D. State Machine . . . . . . . . . . . . . . . . . . . . . 6 D. State Machine . . . . . . . . . . . . . . . . . . . . . 6
E. Pseudocode Implementation . . . . . . . . . . . . . . . 7 E. Pseudocode Implementation . . . . . . . . . . . . . . . 7
5. References . . . . . . . . . . . . . . . . . . . . . . . . 9 5. References . . . . . . . . . . . . . . . . . . . . . . . . 9
Authors' Information . . . . . . . . . . . . . . . . . . . . . 11 Authors' Information . . . . . . . . . . . . . . . . . . . . . 11
MANET Contact Information . . . . . . . . . . . . . . . . . . . 11 MANET Contact Information . . . . . . . . . . . . . . . . . . . 11
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Applicability Statement Applicability Statement
A. Networking Context A. Networking Context
The Intrazone Routing Protocol (IARP) is a limited scope proactive The Intrazone Routing Protocol (IARP) is a limited scope proactive
routing protocol, which is used to support a primary global routing routing protocol, which is used to support a primary global routing
protocol. The scope of the IARP is defined by the routing zone protocol. The scope of the IARP is defined by the routing zone
radius: the distance in hops that IARP route updates are relayed. radius: the distance in hops that IARP route updates are relayed.
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(if so, how?) (if so, how?)
Yes. IARP proactively maintains local routing information Yes. IARP proactively maintains local routing information
(routing zones) based on detected changes in neighbor status. (routing zones) based on detected changes in neighbor status.
* Does the protocol have dependence on a central entity? * Does the protocol have dependence on a central entity?
(if so, how?) (if so, how?)
No. IERP is a fully distributed protocol. No. IERP is a fully distributed protocol.
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* Does the protocol function reactively? (if so, how?) * Does the protocol function reactively? (if so, how?)
No. No.
* Does the protocol function proactively? (if so, how?) * Does the protocol function proactively? (if so, how?)
Yes. IARP proactively maintains LOCAL routing information Yes. IARP proactively maintains LOCAL routing information
(routing zones) for each node. The routing zone information is (routing zones) for each node. The routing zone information is
leveraged, through the bordercasting mechanism, to support leveraged, through the bordercasting mechanism, to support
efficient global propagation of route queries. efficient global propagation of route queries.
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No. It is assumed that security issues are adequately addressed No. It is assumed that security issues are adequately addressed
by the underlying protocols (IPsec, for example). by the underlying protocols (IPsec, for example).
* Does the protocol provide support for utilizing multi-channel, * Does the protocol provide support for utilizing multi-channel,
link-layer technologies? (if so, how?) link-layer technologies? (if so, how?)
Yes. It is assumed that each node's network interface is Yes. It is assumed that each node's network interface is
assigned a unique IP address. assigned a unique IP address.
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1. Introduction 1. Introduction
The design of ad hoc network routing protocols is influenced by link The design of ad hoc network routing protocols is influenced by link
instability (due to node mobility) and limitations in available instability (due to node mobility) and limitations in available
bandwidth and transmission power. Traditional wired networks use bandwidth and transmission power. Traditional wired networks use
proactive routing protocols, like OSPF [7] and RIP [15] to maintain proactive routing protocols, like OSPF [7] and RIP [15] to maintain
up-to-date routes to all networks nodes. More efficient proactive up-to-date routes to all networks nodes. More efficient proactive
routing protocols have been developed for ad hoc networks [1][5][8] routing protocols have been developed for ad hoc networks [1][5][8]
[9][14]. However, continuously tracking the frequent topology changes [9][14]. However, continuously tracking the frequent topology changes
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paths. paths.
Within the context of the ZRP, we refer to the locally proactive Within the context of the ZRP, we refer to the locally proactive
routing component as the Intrazone Routing Protocol (IARP). The IARP routing component as the Intrazone Routing Protocol (IARP). The IARP
is not a specific routing protocol. Rather, it is a family of is not a specific routing protocol. Rather, it is a family of
limited-depth, proactive, link state routing protocols. In this limited-depth, proactive, link state routing protocols. In this
document, we provide an implementation of a simple timer-based IARP. document, we provide an implementation of a simple timer-based IARP.
In addition, we provide a set of basic guidelines which can be used to In addition, we provide a set of basic guidelines which can be used to
convert an existing proactive routing protocol to an IARP. convert an existing proactive routing protocol to an IARP.
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2. Routing Zones and Intrazone Routing 2. Routing Zones and Intrazone Routing
A routing zone for a node X is defined as the set of nodes whose A routing zone for a node X is defined as the set of nodes whose
minimum distance in *hops* from X is no greater than some parameter minimum distance in *hops* from X is no greater than some parameter
referred to as the zone radius. An example of a radius R == 2 hop referred to as the zone radius. An example of a radius R == 2 hop
routing zone (for node A) is shown below. routing zone (for node A) is shown below.
+-----------------------------------------+ +-----------------------------------------+
| +---+ | | +---+ |
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As a result, routing zones of nearby nodes may overlap heavily. As a result, routing zones of nearby nodes may overlap heavily.
Each node proactively tracks the topology of its routing zone through Each node proactively tracks the topology of its routing zone through
an IntrAzone Routing Protocol (IARP). IARP is derived from globally an IntrAzone Routing Protocol (IARP). IARP is derived from globally
proactive link state routing protocols (for example, OSPF). The base proactive link state routing protocols (for example, OSPF). The base
protocol needs to be modified to ensure that the scope of the route protocol needs to be modified to ensure that the scope of the route
updates is restricted to the radius of the node's routing zone. The updates is restricted to the radius of the node's routing zone. The
required modifications and example IARP are described in the next required modifications and example IARP are described in the next
sections. sections.
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3. IARP Conversion Guidelines 3. IARP Conversion Guidelines
Traditional proactive link state protocols can be modified to serve as Traditional proactive link state protocols can be modified to serve as
an IARP by limiting link state updates to the scope of the link an IARP by limiting link state updates to the scope of the link
source's routing zone. The following guidelines can be used to source's routing zone. The following guidelines can be used to
convert existing proactive link state routing protocols to an IARP: convert existing proactive link state routing protocols to an IARP:
- The scope of link state advertisements are limited by a TTL (time - The scope of link state advertisements are limited by a TTL (time
to live) in the link state update packet. The TTL is initialized to to live) in the link state update packet. The TTL is initialized to
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recorded, the routing table is recomputed and the packet's TTL value recorded, the routing table is recomputed and the packet's TTL value
is decremented. As long as the TTL value is greater than 0, the link is decremented. As long as the TTL value is greater than 0, the link
state update packet is rebroadcast. state update packet is rebroadcast.
* This IARP relies on the services of a separate protocol (referred to * This IARP relies on the services of a separate protocol (referred to
here as the Neighbor Discovery Protocol (NDP)) to provide current here as the Neighbor Discovery Protocol (NDP)) to provide current
information about a node's neighbors. At the least, this informa- information about a node's neighbors. At the least, this informa-
tion must include the IP addresses of all the neighbors. IARP and tion must include the IP addresses of all the neighbors. IARP and
NDP can be configured to support supplemental link quality metrics. NDP can be configured to support supplemental link quality metrics.
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A. Packet Format A. Packet Format
1 2 3 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Source Address | | Link Source Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link State Seq Num | Zone Radius | TTL | | Link State Seq Num | Zone Radius | TTL |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RESERVED | RESERVED | Link Dest Cnt | | RESERVED | RESERVED | Link Dest Cnt |
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IP address of the reported link's source node. IP address of the reported link's source node.
* Link State Seq Num (unsigned int) (16 bits) * Link State Seq Num (unsigned int) (16 bits)
Sequence number used to track the link state history of Sequence number used to track the link state history of
the Link Source node. the Link Source node.
* Zone Radius (char) (8 bits) * Zone Radius (char) (8 bits)
Routing zone radius of the link's source node. Determines Routing zone radius of the link's source node. Determines
the extent that link state information propagates. the extent that link state information propagates.
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* TTL (char) (8 bits) * TTL (char) (8 bits)
number of hops remaining until packet is to be discarded number of hops remaining until packet is to be discarded
* Link Dest Count (char) (8 bits) * Link Dest Count (char) (8 bits)
number of link source's neighbors number of link source's neighbors
* Link Destination Address (node_id) (n * 32 bits) * Link Destination Address (node_id) (n * 32 bits)
IP addresses of the link source's neighbor nodes. IP addresses of the link source's neighbor nodes.
* Node/Link Metrics (metric) (n*X * 32 bits) * Node/Link Metrics (metric) (n*X * 32 bits)
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| Addr | | ID | | | | Addr | | ID | | |
| (node_id) | (int) | (int) | (int) | (ls_info list) | | (node_id) | (int) | (int) | (int) | (ls_info list) |
+-----------|--------+-------+--------+------------------| +-----------|--------+-------+--------+------------------|
| | | | | | | | | | | |
|-----------|--------+-------+--------+------------------| |-----------|--------+-------+--------+------------------|
| | | | | | | | | | | |
|-----------|--------+-------+--------+------------------| |-----------|--------+-------+--------+------------------|
| | | | | | | | | | | |
+-----------|--------------------------------------------+ +-----------|--------------------------------------------+
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## detail of (ls_info) data type ## detail of (ls_info) data type
+---+---|---| +---+---|---|
| | ||||| | | |||||
+---+---|---| +---+---|---|
(a) (b) (c) (a) (b) (c)
(a) Link Destination Address (a) Link Destination Address
(b) Link Destination Subnet Mask (b) Link Destination Subnet Mask
(c) Link Metrics (c) Link Metrics
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Event: Link state broadcast timer interrupt. Event: Link state broadcast timer interrupt.
Action: X consults the neighbor discovery process for its Action: X consults the neighbor discovery process for its
own link state (list of neighbors and corresponding own link state (list of neighbors and corresponding
link metrics). X updates its Link State Table and link metrics). X updates its Link State Table and
Routing Table accordingly. The TTL value is Routing Table accordingly. The TTL value is
initialized to R-1 hops (where R is the zone radius). initialized to R-1 hops (where R is the zone radius).
If the TTL is greater than 0 then X loads a link If the TTL is greater than 0 then X loads a link
state packet and broadcasts it to its neighbors. state packet and broadcasts it to its neighbors.
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D.2 D.2
Event: An IARP link state packet is received. Event: An IARP link state packet is received.
Action: The link state update is recorded in the Link State Action: The link state update is recorded in the Link State
Table and the Routing Table is updated accordingly. Table and the Routing Table is updated accordingly.
The TTL is decremented. If the TTL is greater The TTL is decremented. If the TTL is greater
than 0 then X broadcasts the link state packet to than 0 then X broadcasts the link state packet to
its neighbors. its neighbors.
D.3 D.3
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{ {
link_source = MY_ID; link_source = MY_ID;
Neighbor_State(&neighbor[n],&mask[n],&metrics[n][x]); Neighbor_State(&neighbor[n],&mask[n],&metrics[n][x]);
TTL = R; TTL = R;
} }
// Record link state information in Link State Table // Record link state information in Link State Table
add(Link_State_Table, link_source, link_dest, mask, radius, add(Link_State_Table, link_source, link_dest, mask, radius,
link_metric, state_id, flags); link_metric, state_id, flags);
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// Recompute Routing Table // Recompute Routing Table
Routing_Table =compute_routes_from_links(Link_State_Table,node); Routing_Table =compute_routes_from_links(Link_State_Table,node);
// Report Routing Table update to IERP // Report Routing Table update to IERP
IARP_updated(); IARP_updated();
// Relay link state update only if link source lies inside of // Relay link state update only if link source lies inside of
// of routing zone (evaluated based on TTL value) // of routing zone (evaluated based on TTL value)
TTL--; TTL--;
if(TTL > 0) if(TTL > 0)
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if(current_time()-insert_time > LINK_STATE_LIFETIME) if(current_time()-insert_time > LINK_STATE_LIFETIME)
remove_from_table(Link_State_Table, link_source); remove_from_table(Link_State_Table, link_source);
} }
// Recompute Routing Table // Recompute Routing Table
Routing_Table = compute_routes_from_links(Link_State_Table,node); Routing_Table = compute_routes_from_links(Link_State_Table,node);
// Report Routing Table update to IERP // Report Routing Table update to IERP
IARP_updated(); IARP_updated();
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5. References 5. References
[1] Garcia-Luna-Aceves, J.J. and Spohn, M., "Efficient Routing in [1] Garcia-Luna-Aceves, J.J. and Spohn, M., "Efficient Routing in
Packet-Radio Networks Using Link-State Information," Packet-Radio Networks Using Link-State Information,"
WCNC '99, September 1999. WCNC '99, September 1999.
[2] Haas, Z.J., Pearlman, M.R. and Samar, P., "Bordercast Resolution [2] Haas, Z.J., Pearlman, M.R. and Samar, P., "Bordercast Resolution
Protocol (BRP)," IETF Internet Draft, Protocol (BRP)," IETF Internet Draft,
draft-ietf-manet-brp-00.txt, January 2001. draft-ietf-manet-brp-01.txt, June 2001.
[3] Haas, Z.J., Pearlman, M.R. and Samar, P., "Interzone Routing [3] Haas, Z.J., Pearlman, M.R. and Samar, P., "Interzone Routing
Protocol (IERP)," IETF Internet Draft, Protocol (IERP)," IETF Internet Draft,
draft-ietf-manet-ierp-00.txt, January 2001. draft-ietf-manet-ierp-01.txt, June 2001.
[4] Haas, Z.J., Pearlman, M.R. and Samar, P., "Zone Routing Protocol [4] Haas, Z.J., Pearlman, M.R. and Samar, P., "Zone Routing Protocol
(ZRP)," IETF Internet Draft, draft-ietf-manet-zrp-04.txt, (ZRP)," IETF Internet Draft, draft-ietf-manet-zrp-04.txt,
January 2001. January 2001.
[5] Jacquet, P., Muhlethaler, P., Qayyum A., Laouiti A., Viennot L., [5] Jacquet, P., Muhlethaler, P., Qayyum A., Laouiti A., Viennot L.,
and Clausen T., "Optimized Link State Routing Protocol," and Clausen T., "Optimized Link State Routing Protocol,"
IETF Internet Draft, draft-ietf-manet-olsr-03.txt, IETF Internet Draft, draft-ietf-manet-olsr-03.txt,
November 2000. November 2000.
[6] Johnson, D.B. and Maltz, D.A., "Dynamic Source Routing in Ad-Hoc [6] Johnson, D.B. and Maltz, D.A., "Dynamic Source Routing in Ad-Hoc
skipping to change at line 641 skipping to change at line 641
Routing Algorithm for Mobile Wireless Networks," Routing Algorithm for Mobile Wireless Networks,"
IEEE INFOCOM'97, Kobe, Japan, 1997. IEEE INFOCOM'97, Kobe, Japan, 1997.
[11] Pearlman, M.R. and Haas, Z.J., "Determining the Optimal [11] Pearlman, M.R. and Haas, Z.J., "Determining the Optimal
Configuration for the Zone Routing Protocol," IEEE JSAC, Configuration for the Zone Routing Protocol," IEEE JSAC,
August, 1999. August, 1999.
[12] Pearlman, M.R., Haas, Z.J. and S.I. Mir, "Using Routing Zones to [12] Pearlman, M.R., Haas, Z.J. and S.I. Mir, "Using Routing Zones to
Support Route Maintenance in Ad Hoc Networks," Support Route Maintenance in Ad Hoc Networks,"
IEEE WCNC 2000, Chicago, IL, Sept. 2000. IEEE WCNC 2000, Chicago, IL, Sept. 2000.
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[13] Perkins, C.E. and Royer, E.M., "Ad Hoc On-Demand Distance [13] Perkins, C.E. and Royer, E.M., "Ad Hoc On-Demand Distance
Vector Routing," IEEE WMCSA'99, New Orleans, LA, Feb. 1999 Vector Routing," IEEE WMCSA'99, New Orleans, LA, Feb. 1999
[14] Perkins, C.E. and Bhagwat, P., "Highly Dynamic [14] Perkins, C.E. and Bhagwat, P., "Highly Dynamic
Destination-Sequenced Distance-Vector Routing (DSDV) for Destination-Sequenced Distance-Vector Routing (DSDV) for
Mobile Computers," ACM SIGCOMM, vol.24, no.4, October 1994. Mobile Computers," ACM SIGCOMM, vol.24, no.4, October 1994.
[15] Postel, J., "Internet Protocol," RFC 791, Sept. 1981. [15] Postel, J., "Internet Protocol," RFC 791, Sept. 1981.
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Authors' Information Authors' Information
Zygmunt J. Haas Zygmunt J. Haas
Wireless Networks Laboratory Wireless Networks Laboratory
323 Frank Rhodes Hall 323 Frank Rhodes Hall
School of Electrical Engineering School of Electrical Engineering
Cornell University Cornell University
Ithaca, NY 14853 Ithaca, NY 14853
United States of America tel: (607) 255-3454, fax: (607) 255-9072 United States of America tel: (607) 255-3454, fax: (607) 255-9072
skipping to change at line 698 skipping to change at line 698
(301) 405-6630 (301) 405-6630
corson@isr.umd.edu corson@isr.umd.edu
Joseph Macker Joseph Macker
Information Technology Division Information Technology Division
Naval Research Laboratory Naval Research Laboratory
Washington, DC 20375 Washington, DC 20375
(202) 767-2001 (202) 767-2001
macker@itd.nrl.navy.mil macker@itd.nrl.navy.mil
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