871:, where the two halves of a connection can use different relays, traffic between a native IPv6 host and a Teredo client uses the same Teredo relay, namely the one closest to the native IPv6 host network-wise. The Teredo client cannot localize a relay by itself (since it cannot send IPv6 packets by itself). If it needs to initiate a connection to a native IPv6 host, it sends the first packet through the Teredo server, which sends a packet to the native IPv6 host using the client's Teredo IPv6 address. The native IPv6 host then responds as usual to the client's Teredo IPv6 address, which eventually causes the packet to find a Teredo relay, which initiates a connection to the client (possibly using the Teredo server for
338:
1233:(a kind of marine wood-boring clam) bores tunnels through wood. Shipworms have been responsible for the loss of many wooden hulls. Christian Huitema, in the original draft, noted that the shipworm "only survives in relatively clean and unpolluted water; its recent comeback in several Northern American harbors is a testimony to their newly retrieved cleanliness. The Shipworm service should, in turn, contributes [
417:: Teredo implementation should provide a way to stop using Teredo connectivity when IPv6 matures and connectivity becomes available using a less brittle mechanism. As of IETF89, Microsoft plans to deactivate their Teredo servers for Windows clients in the first half of 2014 (exact date TBD), and encourage the deactivation of publicly operated Teredo relays.
875:). The Teredo Client and native IPv6 host then use the relay for communication as long as they need to. This design means that neither the Teredo server nor client needs to know the IPv4 address of any Teredo relays. They find a suitable one automatically via the global IPv6 routing table, since all Teredo relays advertise the network 2001::/32.
852:) a route toward the Teredo IPv6 prefix (2001::/32) to other IPv6 hosts. That way, the Teredo relay receives traffic from the IPv6 hosts addressed to any Teredo client, and forwards it over UDP/IPv4. Symmetrically, it receives packets from Teredo clients addressed to native IPv6 hosts over UDP/IPv4 and injects those into the native IPv6 network.
808:) toward the IPv6 node, and sends it through its configured Teredo server. The Teredo server de-capsulates the ping onto the IPv6 Internet, so that the ping should eventually reach the IPv6 node. The IPv6 node should then reply with an ICMPv6 Echo Reply, as mandated by RFC 2460. This reply packet is routed to the
409:
Teredo alleviates this problem by encapsulating IPv6 packets within UDP/IPv4 datagrams, which most NATs can forward properly. Thus, IPv6-aware hosts behind NATs can serve as Teredo tunnel endpoints even when they don't have a dedicated public IPv4 address. In effect, a host that implements Teredo can
1066:
by assigning globally routable IPv6 addresses to network hosts behind NAT devices, which would otherwise be unreachable from the
Internet. By doing so, Teredo potentially exposes any IPv6-enabled application with an open port to the outside. Teredo tunnel encapsulation can also cause the contents of
997:
in Taiwan later proposed SymTeredo, which enhanced the original Teredo protocol to support symmetric NATs, and the
Microsoft and Miredo implementations implement certain unspecified non-standard extensions to improve support for symmetric NATs. However, connectivity between a Teredo client behind a
949:
It is expected that large network operators will maintain Teredo relays. As with 6to4, it remains unclear how well the Teredo service will scale up if a large proportion of
Internet hosts start using IPv6 through Teredo in addition to IPv4. While Microsoft has operated a set of Teredo servers since
505:
A Teredo relay whose range of service is limited to the very host it runs on. As such, it has no particular bandwidth or routing requirements. A computer with a host-specific relay uses Teredo to communicate with Teredo clients, but sticks to its main IPv6 connectivity provider to reach the rest of
1001:
Indeed, Teredo assumes that when two clients exchange encapsulated IPv6 packets, the mapped/external UDP port numbers used will be the same as those that were used to contact the Teredo server (and building the Teredo IPv6 address). Without this assumption, it would not be possible to establish a
475:
A well-known host used for initial configuration of a Teredo tunnel. A Teredo server never forwards any traffic for the client (apart from IPv6 pings), and has therefore modest bandwidth requirements (a few hundred bits per second per client at most), which means a single server can support many
1006:. A Teredo implementation tries to detect the type of NAT at startup, and will refuse to operate if the NAT appears to be symmetric. (This limitation can sometimes be worked around by manually configuring a port forwarding rule on the NAT box, which requires administrative access to the device).
406:. In such a situation, the only available public IPv4 address is assigned to the NAT device, and the 6to4 tunnel endpoint must be implemented on the NAT device itself. The problem is that many NAT devices currently deployed cannot be upgraded to implement 6to4, for technical or economic reasons.
1157:
have built-in support for Teredo with an unspecified extension for symmetric NAT traversal. However, if only a link-local and Teredo address are present, these operating systems don't try to resolve IPv6 DNS AAAA records if a DNS A record is present, in which case they use IPv4. Therefore, only
1090:
For a Teredo pseudo-tunnel to operate properly, outgoing UDP packets to port 3544 must be unfiltered. Moreover, replies to these packets (i.e., "solicited traffic") must also be unfiltered. This corresponds to the typical setup of a NAT and its stateful firewall functionality. Teredo tunneling
488:
The remote end of a Teredo tunnel. A Teredo relay must forward all of the data on behalf of the Teredo clients it serves, with the exception of direct Teredo client to Teredo client exchanges. Therefore, a relay requires a lot of bandwidth and can only support a limited number of simultaneous
1009:
Teredo can only provide a single IPv6 address per tunnel endpoint. As such, it is not possible to use a single Teredo tunnel to connect multiple hosts, unlike 6to4 and some point-to-point IPv6 tunnels. The bandwidth available to all Teredo clients toward the IPv6 Internet is limited by the
855:
In practice, network administrators can set up a private Teredo relay for their company or campus. This provides a short path between their IPv6 network and any Teredo client. However, setting up a Teredo relay on a scale beyond that of a single network requires the ability to export
815:
Maintaining a Teredo server requires little bandwidth, because they are not involved in actual transmission and reception of IPv6 traffic packets. Also, it does not involve any access to the
Internet routing protocols. The only requirements for a Teredo server are:
533:, 0 otherwise, but RFC 5991 changed it to always be 0 to avoid revealing this fact to strangers. The "R" bit is currently unassigned and should be sent as 0. The "U" and "G" bits are set to 0 to emulate the "Universal/local" and "Group/individual" bits in
878:
On March 30, 2006, Italian ISP ITGate was the first AS to start advertising a route toward 2001::/32 on the IPv6 Internet, so that RFC 4380-compliant Teredo implementations would be fully usable. As of 16 February 2007, it is no longer functional.
1067:
the IPv6 data traffic to become invisible to packet inspection software, facilitating the spread of malware. Finally, Teredo exposes the IPv6 stack and the tunneling software to attacks should they have any remotely exploitable vulnerability.
1081:
The Teredo protocol also encapsulates detailed information about the tunnel's endpoint in its data packets. This information can help potential attackers by increasing the feasibility of an attack, and/or by reducing the effort required.
537:. The 12 "A" bits were 0 in the original RFC 4380 specification, but were changed to random bits chosen by the Teredo client in RFC 5991 to provide the Teredo node with additional protection against IPv6-based scanning attacks.
402:, the most common IPv6 over IPv4 tunneling protocol, requires that the tunnel endpoint have a public IPv4 address. However, many hosts currently attach to the IPv4 Internet through one or several NAT devices, usually because of
781:. Teredo clients also maintain a binding on their NAT toward their Teredo server by sending a UDP packet at regular intervals. That ensures that the server can always contact any of its clients—which is required for
462:
A host that has IPv4 connectivity to the
Internet from behind a NAT and uses the Teredo tunneling protocol to access the IPv6 Internet. Teredo clients are assigned an IPv6 address that starts with the Teredo prefix
1621:
799:
Teredo servers can also transmit ICMPv6 packet from Teredo clients toward the IPv6 Internet. In practice, when a Teredo client wants to contact a native IPv6 node, it must locate the corresponding Teredo relay,
823:
Two distinct public IPv4 addresses. Though not written down in the official specification, Microsoft
Windows clients expect both addresses to be consecutive — the second IPv4 address is for NAT detection
1556:
1035:
tunnels can be more reliable and are more accountable than Teredo, and typically provide permanent IPv6 addresses that do not depend on the IPv4 address of the tunnel endpoint. Some point-to-point
1074:
option. This allows applications to specify from which sources they are willing to accept IPv6 traffic: from the Teredo tunnel, from anywhere except Teredo (the default), or only from the local
529:
Bits 64 to 79 hold some flags and other bits; the format for these 16 bits, MSB first, is "CRAAAAUG AAAAAAAA". The "C" bit was set to 1 if the Teredo client is located behind a
304:
Teredo is a temporary measure. In the long term, all IPv6 hosts should use native IPv6 connectivity. Teredo should be disabled when native IPv6 connectivity becomes available.
1611:
987:
1586:
1552:
1334:
1422:
220:
1099:
In 2010, new methods to create denial of service attacks via routing loops that use Teredo tunnels were uncovered. They are relatively easy to prevent.
990:. The Shipworm specification original that led to the final Teredo protocol also supported symmetric NATs, but dropped that due to security concerns.
1531:
1455:
1725:
792:
packet to the client's Teredo server, whose IP address it infers from the Teredo IPv6 address of the Teredo client. The server then forwards the
1372:
For the time being, teredo.remlab.net will alias the public Teredo server provided by the TREX regional exchange in the
Finnish city of Tampere.
950:
they released the first Teredo pseudo-tunnel for
Windows XP, they have never provided a Teredo relay service for the IPv6 Internet as a whole.
958:
Officially, this mechanism was created for
Microsoft Windows XP and onwards PCs to provide IPv6 connectivity to IPv4 clients by connecting to
982:
Teredo is not compatible with all NAT devices. Using the terminology of RFC 3489, it supports full cone, restricted, and port-restricted
1750:
1779:
85:
804:, to which public IPv4 and UDP port number to send encapsulated IPv6 packets. To do that, the client crafts an ICMPv6 Echo Request (
1206:
213:
137:
1110:
as of
Windows 10, version 1803 and later disable Teredo by default. If needed, this transitional technology can be enabled via a
56:
1027:
requires a public IPv4 address, but provides a large 48-bit IPv6 prefix for each tunnel endpoint, and has a lower encapsulation
530:
1650:
1043:
protocol can do this). On the other hand, point-to-point tunnels normally require registration. Automated tools (for instance
413:
In the long term, all IPv6 hosts should use native IPv6 connectivity. The temporary Teredo protocol includes provisions for a
1816:
1283:
Sharma, Vishal; Kumar, Rajesh (2017). "Teredo tunneling-based secure transmission between UAVs and ground ad hoc networks".
1695:
1500:
644:
Is probably (99.98%) not compliant with RFC 5991 (the 12 random bits are all 0, which happens less than 0.025% of the time)
983:
429:
Diagnoses UDP over IPv4 (UDPv4) connectivity and discovers the kind of NAT present (using a simplified replacement to the
1360:
777:
Teredo clients use Teredo servers to autodetect the kind of NAT they are behind (if any), through a simplified STUN-like
206:
1578:
1785:
385:
359:
367:
1762:
1758:
1721:
1415:
1392:
1326:
1811:
1168:
version 1803 and later disable Teredo by default. If needed, this transitional technology can be enabled via a
994:
363:
194:
189:
1553:"IPv6 Tunneling Protocols: Good for Adoption, Not So Hot for Security - TrendLabs Security Intelligence Blog"
142:
75:
1821:
1675:
998:
symmetric NAT, and a Teredo client behind a port-restricted or symmetric NAT remains seemingly impossible.
861:
788:
If a Teredo relay (or another Teredo client) must send an IPv6 packet to a Teredo client, it first sends a
264:
90:
1521:
1448:
630:
As an example, the IPv6 address 2001:0000:4136:e378:8000:63bf:3fff:fdd2 refers to a Teredo client that:
544:
UDP port number. This is the port number that the NAT maps to the Teredo client, with all bits inverted.
1713:
654:
Has a NAT public IPv4 address of 192.0.2.45 (not 3ffffdd2 equals c000022d, which is to say, 192.0.2.45)
282:
245:
439:
Encapsulates IPv6 packets inside UDPv4 datagrams for transmission over an IPv4 network (this includes
1019:
796:
to the client, so the Teredo client software knows it must do hole punching toward the Teredo relay.
490:
22:
348:
111:
1032:
1002:
direct communication between the two clients, and a costly relay would have to be used to perform
403:
352:
1169:
1111:
317:
290:
489:
clients. Each Teredo relay serves a range of IPv6 hosts (e.g. a single campus or company, an
106:
61:
1612:"DirectAccess clients that use Teredo tunneling cannot connect after upgrade to Windows 10"
1040:
1028:
271:
8:
1140:
1070:
In order to reduce the attack surface, the Microsoft IPv6 stack has a "protection level"
895:
1010:
availability of Teredo relays, which are no different than 6to4 relays in that respect.
480:
manner, thus using the same amount of memory regardless of how many clients it supports.
1308:
883:
839:
teredo.remlab.net / teredo-debian.remlab.net (Germany), now redirects to teredo.trex.fi
820:
The ability to emit ICMPv6 packets with a source address belonging to the Teredo prefix
477:
274:
41:
1130:
1642:
1492:
1300:
1107:
919:
782:
305:
641:
Is behind a cone NAT and client is not fully compliant with RFC 5991 (bit 64 is set)
1484:
1312:
1292:
1252:
1159:
1071:
1003:
446:
Routes traffic between Teredo hosts and native (or otherwise non-Teredo) IPv6 hosts
321:
259:
but have no native connection to an IPv6 network. Unlike similar protocols such as
234:
173:
1091:
software reports a fatal error and stops if outgoing IPv4 UDP traffic is blocked.
848:
A Teredo relay potentially requires much network bandwidth. Also, it must export (
1699:
1679:
1459:
497:); it forwards traffic between any Teredo clients and any host within said range.
132:
1692:
1579:"Internet-Draft - Teredo routing loops - Mitigating Teredo Rooting Loop Attacks"
551:
IPv4 address. This is the public IPv4 address of the NAT with all bits inverted.
1616:
1488:
1472:
1262:
1229:. The idea was that the protocol would pierce through NAT devices, much as the
1062:
526:
Bits 32 to 63 embed the primary IPv4 address of the Teredo server that is used.
410:
gain IPv6 connectivity with no cooperation from the local network environment.
1356:
1216:
and a userland Teredo server, developed at the National Chiao Tung University.
890:
implementation and advertising 2001::/32 globally. The relays were located in
812:
Teredo relay, which — finally — tries to contact the Teredo client.
1805:
1496:
1304:
1243:
1158:
literal IPv6 URLs typically use Teredo. This behavior can be modified in the
1150:
1036:
915:
872:
494:
440:
294:
147:
127:
297:
and through NAT devices. Teredo nodes elsewhere on the IPv6 network (called
1791:
Teredo: Tunneling IPv6 over UDP through Network Address Translations (NATs)
1213:
1173:
1115:
516:
1526:
899:
648:
635:
534:
519:, which is constructed as follows (the higher order bit is numbered 0):
1165:
1384:
1796:
1416:"Hurricane Electric's experience in deploying Teredo and 6to4 relays"
1296:
1154:
1144:
943:
939:
935:
476:
clients. Additionally, a Teredo server can be implemented in a fully
436:
Assigns a globally routable unique IPv6 address to each host using it
309:
242:
337:
1230:
1198:
1191:
1075:
1039:
also support UDP encapsulation to traverse NATs (for instance, the
286:
256:
1714:"Shipworm: Tunneling IPv6 over UDP through NATs (draft 00 of 08)"
1202:
911:
903:
891:
887:
1672:
1137:
relay (also in the Advanced Networking Pack for Service Pack 1).
1473:"Enhancing teredo IPv6 tunneling to traverse the symmetric NAT"
1179:
927:
907:
152:
51:
301:) receive the packets, un-encapsulate them, and pass them on.
1671:
Kabassanov, Konstantin; Jardin, Vincent. (October 22, 2003).
1257:
1183:
1044:
931:
923:
168:
71:
1187:
1126:
Several implementations of Teredo are currently available:
1024:
971:
868:
430:
399:
313:
278:
260:
253:
249:
66:
46:
36:
1239:] to a newly retrieved transparency of the Internet."
1225:
The initial nickname of the Teredo tunneling protocol was
316:
standardized it as RFC 4380. The Teredo server listens on
1471:
Huang, Shiang-Ming; Wu, Quincy; Lin, Yi-Bing (May 2006).
1421:. LACNIC-XII/FLIP6 2009 Conference, Panama City, Panama.
1235:
857:
634:
Uses Teredo server at address 65.54.227.120 (4136e378 in
1085:
647:
Uses UDP mapped port 40000 on its NAT (in hexadecimal
16:
Protocol transition technology in computer networking
293:(UDP) packets. Teredo routes these datagrams on the
252:
connectivity for IPv6-capable hosts that are on the
1354:
1246:, Huitema later changed the protocol's name from
455:Teredo defines several different kinds of nodes:
1803:
523:Bits 0 to 31 hold the Teredo prefix (2001::/32).
425:The Teredo protocol performs several functions:
493:or a whole operator network, or even the whole
263:, it can perform its function even from behind
1450:Shipworm: Tunneling IPv6 over UDP through NATs
1385:"IT.Gate | Technology Services - IT.Gate"
1285:International Journal of Communication Systems
1047:) make it easy to use Point-to-Point tunnels.
281:(Internet Protocol version 6) connectivity by
214:
1413:
1102:
1282:
366:. Unsourced material may be challenged and
1470:
1143:has a relay and server provided under the
1050:
651:63bf equals 9c40, or decimal number 40000)
221:
207:
1197:ng_teredo is a relay and server based on
386:Learn how and when to remove this message
1094:
515:Each Teredo client is assigned a public
1797:JavaScript Teredo-IP address calculator
1748:
1744:
1742:
1711:
1691:"Solomon, Aaron". (November 29, 2004).
1446:
1804:
1793:. RFC 4380, C. Huitema. February 2006.
1653:from the original on November 1, 2019
1606:
1604:
1589:from the original on December 7, 2021
1220:
267:(NAT) devices such as home routers.
1739:
1577:Gont, Fernando (September 8, 2010).
1576:
1447:Huitema, Christian (July 12, 2001).
1086:Firewalling, filtering, and blocking
364:adding citations to reliable sources
331:
1514:
1428:from the original on April 11, 2015
1355:RĂ©mi Denis-Courmont (5 June 2021).
1182:is a client, relay, and server for
13:
1601:
1395:from the original on June 14, 2021
1121:
968:Teredo Tunneling Adapter Interface
510:
14:
1833:
1786:Current anycast Teredo BGP routes
1773:
1749:Huitema, Christian (2001-12-19).
1712:Huitema, Christian (2001-08-25).
974:port on the router for relaying.
970:driver. The service also opens a
336:
1759:Internet Engineering Task Force
1728:from the original on 2021-08-29
1722:Internet Engineering Task Force
1705:
1685:
1665:
1635:
1624:from the original on 2021-01-14
1570:
1559:from the original on 2016-10-08
1534:from the original on 2020-08-10
1503:from the original on 2022-05-01
1363:from the original on 2022-07-17
1337:from the original on 2016-12-23
1212:NICI-Teredo is a relay for the
1013:
886:enabled 14 Teredo relays in an
1751:"Renaming Shipworm as Teredo?"
1545:
1464:
1440:
1407:
1377:
1348:
1319:
1276:
995:National Chiao Tung University
986:devices, but does not support
977:
962:and works in conjunction with
835:Former public Teredo servers:
1:
1414:Levy, Martin (May 28, 2009).
1269:
450:
1817:IPv6 transition technologies
1327:"Teredo Addresses (Windows)"
556:Teredo IPv6 addressing table
7:
1522:"Malware Tunneling in IPv6"
1477:IEEE Communications Letters
1055:
547:Bits 96 to 127 contain the
420:
265:network address translation
10:
1838:
1489:10.1109/LCOMM.2006.1633339
1017:
953:
882:In Q1 2009, IPv6 backbone
772:
540:Bits 80 to 95 contain the
502:Teredo host-specific relay
327:
23:IPv6 transition mechanisms
1755:IETF NGTrans mailing list
1103:Default use in MS-Windows
1020:IPv6 transition mechanism
860:IPv6 routes to the other
843:
659:Teredo IPv6 example table
1458:January 4, 2021, at the
1242:To avoid confusion with
831:teredo.trex.fi (Finland)
270:Teredo operates using a
1643:"ISP Column - May 2011"
1585:. ietf.org. p. 2.
1051:Security considerations
827:Public Teredo servers:
779:qualification procedure
1761:(IETF). Archived from
1133:includes a client and
291:User Datagram Protocol
1812:Internet architecture
1260:name of the shipworm
1209:University and 6WIND.
1095:DoS via routing loops
1060:Teredo increases the
404:IPv4 address shortage
246:transition technology
1782:on Microsoft TechNet
1357:"Miredo : News"
360:improve this section
308:developed Teredo at
289:packets within IPv4
272:platform independent
1822:Tunneling protocols
1765:on January 8, 2018.
1141:Windows Server 2003
235:computer networking
1698:2021-08-29 at the
1678:2005-03-06 at the
1673:Teredo for FreeBSD
1331:msdn.microsoft.com
1221:Choice of the name
960:ipv6.microsoft.com
884:Hurricane Electric
862:autonomous systems
785:to work properly.
506:the IPv6 Internet.
275:tunneling protocol
42:Lightweight 4over6
1530:. June 22, 2012.
1108:Microsoft Windows
783:NAT hole punching
770:
769:
725:Obfuscated Client
628:
627:
622:Obfuscated Client
396:
395:
388:
306:Christian Huitema
231:
230:
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1718:Ietf Datatracker
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1583:Ietf Datatracker
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1297:10.1002/dac.3144
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1004:triangle routing
663:
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560:
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415:sunset procedure
391:
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248:that gives full
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1780:Teredo Overview
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1771:
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1731:
1729:
1710:
1706:
1700:Wayback Machine
1690:
1686:
1682:www-rp.lip6.fr.
1680:Wayback Machine
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1460:Wayback Machine
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1122:Implementations
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511:IPv6 addressing
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29:Standards Track
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1774:External links
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1702:. Sourceforge.
1684:
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1634:
1620:. 2020-12-07.
1617:Microsoft Docs
1600:
1569:
1555:. 2009-10-26.
1544:
1513:
1483:(5): 408–410.
1463:
1439:
1406:
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1318:
1274:
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1271:
1268:
1263:Teredo navalis
1244:computer worms
1222:
1219:
1218:
1217:
1210:
1195:
1177:
1163:
1148:
1138:
1131:Windows XP SP2
1123:
1120:
1104:
1101:
1096:
1093:
1087:
1084:
1063:attack surface
1057:
1054:
1052:
1049:
1037:tunnel brokers
1033:Point-to-point
1018:Main article:
1015:
1012:
993:People at the
988:symmetric NATs
979:
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955:
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376:September 2021
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1657:September 22,
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1399:September 22,
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1151:Windows Vista
1149:
1147:Beta program.
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1135:host-specific
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797:
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791:
790:Teredo bubble
786:
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765:
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759:
757:65.54.227.120
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535:MAC addresses
532:
528:
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522:
521:
520:
518:
504:
501:
500:
496:
495:IPv6 Internet
492:
487:
484:
483:
479:
474:
472:Teredo server
471:
470:
461:
459:Teredo client
458:
457:
456:
445:
442:
441:NAT traversal
438:
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432:
428:
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418:
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411:
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401:
390:
387:
379:
369:
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354:
350:
345:This section
343:
339:
334:
333:
325:
323:
319:
315:
311:
307:
302:
300:
299:Teredo relays
296:
295:IPv4 Internet
292:
288:
284:
283:encapsulating
280:
276:
273:
268:
266:
262:
258:
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154:
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149:
148:Public 4over6
146:
144:
141:
139:
136:
134:
131:
129:
128:Tunnel broker
126:
125:
124:
123:
120:Informational
119:
118:
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108:
105:
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102:
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35:
34:
33:
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28:
27:
24:
21:
20:
1790:
1763:the original
1754:
1730:. Retrieved
1717:
1707:
1687:
1667:
1655:. Retrieved
1646:
1637:
1626:. Retrieved
1615:
1591:. Retrieved
1582:
1572:
1561:. Retrieved
1547:
1536:. Retrieved
1525:
1516:
1505:. Retrieved
1480:
1476:
1466:
1449:
1442:
1432:December 29,
1430:. Retrieved
1409:
1397:. Retrieved
1388:
1379:
1371:
1365:. Retrieved
1350:
1339:. Retrieved
1330:
1321:
1291:(7): e3144.
1288:
1284:
1278:
1261:
1256:, after the
1251:
1247:
1241:
1234:
1226:
1224:
1214:Linux kernel
1174:Group Policy
1134:
1125:
1116:Group Policy
1106:
1098:
1089:
1080:
1069:
1061:
1059:
1023:
1014:Alternatives
1008:
1000:
992:
981:
967:
966:service and
963:
959:
957:
948:
881:
877:
873:NAT piercing
866:
854:
849:
847:
834:
826:
814:
809:
805:
801:
798:
793:
789:
787:
778:
776:
727:public IPv4
658:
629:
624:public IPv4
555:
548:
541:
517:IPv6 address
514:
485:Teredo relay
454:
424:
414:
412:
408:
397:
382:
373:
358:Please help
346:
303:
298:
269:
238:
232:
99:Experimental
80:
1693:NICI-Teredo
1647:potaroo.net
1527:US-CERT.gov
1172:command or
1114:command or
978:Limitations
900:Los Angeles
766:192.0.2.45
714:server IPv4
706:Description
636:hexadecimal
611:server IPv4
603:Description
1806:Categories
1732:2021-08-09
1628:2021-01-12
1563:2016-09-05
1538:2016-09-05
1507:2022-05-01
1367:2022-07-17
1341:2014-12-02
1270:References
1166:Windows 10
747:3fff:fdd2
720:Obfuscated
617:Obfuscated
549:obfuscated
542:obfuscated
451:Node types
312:, and the
182:Deprecated
1593:August 9,
1497:1089-7798
1389:itgate.it
1305:1099-1131
1205:from the
1155:Windows 7
1145:Microsoft
964:IP Helper
944:Hong Kong
940:Frankfurt
936:Amsterdam
850:advertise
738:4136:e378
735:2001:0000
681:96 - 127
578:96 - 127
478:stateless
465:2001::/32
433:protocol)
347:does not
310:Microsoft
243:Microsoft
1726:Archived
1724:(IETF).
1696:Archived
1676:Archived
1651:Archived
1622:Archived
1587:Archived
1557:Archived
1532:Archived
1501:Archived
1456:Archived
1423:Archived
1393:Archived
1361:Archived
1335:Archived
1248:Shipworm
1231:shipworm
1227:Shipworm
1199:netgraph
1192:Mac OS X
1160:registry
1076:intranet
1056:Exposure
1029:overhead
916:New York
864:(AS's).
760:cone NAT
722:UDP port
701:32 bits
619:UDP port
598:32 bits
531:cone NAT
421:Overview
287:datagram
257:Internet
1313:5263153
1203:FreeBSD
954:Clients
920:Ashburn
912:Toronto
904:Chicago
896:Fremont
892:Seattle
888:anycast
867:Unlike
810:closest
773:Servers
752:Decoded
698:16 bits
695:16 bits
692:32 bits
689:32 bits
678:80 - 95
675:64 - 79
672:32 - 63
595:16 bits
592:16 bits
589:32 bits
586:32 bits
575:80 - 95
572:64 - 79
569:32 - 63
368:removed
353:sources
328:Purpose
195:NAPT-PT
143:464XLAT
57:DS-Lite
1495:
1311:
1303:
1253:Teredo
1190:, and
1180:Miredo
1072:socket
942:, and
928:London
908:Dallas
844:Relays
794:bubble
712:Teredo
709:Prefix
686:Length
669:0 - 31
609:Teredo
606:Prefix
583:Length
566:0 - 31
239:Teredo
190:NAT-PT
161:Drafts
153:ISATAP
81:Teredo
52:6over4
1426:(PDF)
1419:(PDF)
1309:S2CID
1258:genus
1184:Linux
1045:AICCU
1041:AYIYA
932:Paris
924:Miami
763:40000
717:Flags
614:Flags
320:port
285:IPv6
241:is a
169:AYIYA
76:DNS64
72:NAT64
1659:2019
1595:2021
1493:ISSN
1434:2012
1401:2019
1301:ISSN
1207:LIP6
1201:for
1188:*BSD
1153:and
1025:6to4
972:UPNP
869:6to4
806:ping
802:i.e.
744:63bf
741:8000
732:Part
666:Bits
563:Bits
431:STUN
400:6to4
398:For
351:any
349:cite
322:3544
314:IETF
279:IPv6
261:6to4
254:IPv4
250:IPv6
174:dIVI
86:SIIT
67:6to4
47:6in4
37:4in6
1485:doi
1293:doi
1250:to
1236:sic
1170:CLI
1112:CLI
984:NAT
858:BGP
649:not
491:ISP
362:by
318:UDP
233:In
138:TRT
133:IVI
112:4rd
107:TSP
91:MAP
62:6rd
1808::
1757:.
1753:.
1741:^
1720:.
1716:.
1649:.
1645:.
1614:.
1603:^
1581:.
1524:.
1499:.
1491:.
1481:10
1479:.
1475:.
1391:.
1387:.
1370:.
1359:.
1333:.
1329:.
1307:.
1299:.
1289:30
1287:.
1266:.
1186:,
1118:.
1078:.
1031:.
946:.
938:,
934:,
930:,
926:,
922:,
918:,
914:,
910:,
906:,
902:,
898:,
894:,
467:).
324:.
237:,
74:/
1735:.
1661:.
1631:.
1597:.
1566:.
1541:.
1510:.
1487::
1453:.
1436:.
1403:.
1344:.
1315:.
1295::
1194:,
1176:.
1162:.
638:)
463:(
443:)
389:)
383:(
378:)
374:(
370:.
356:.
222:e
215:t
208:v
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.