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Questions tagged [ipv6]

For questions about Internet Protocol version 6 (IPv6); as specified in RFC2460.

2
votes
1answer
56 views

Setting Destination MAC address for RTP/UDP packets

I have a requirement where I have to send the UDP packet to a destination multicast IPv6 address. In addition to that the packets must also have corresponding destination multicast MAC address set. I ...
1
vote
1answer
33 views

Does CSR1000v on AWS support IPv6?

I'm trying to implement Segment Routing IPv6 (SRv6) in Cisco CSR1000v on AWS. I'm having issues with IPv6 which gave the impression that IPv6 data plane does not work. Similarly, I configured a ...
3
votes
1answer
37 views

How to handle IPv6 Extension Header Options with action = 01

RFC 8200 section 4.2 states that if a node does not recognize an option type, that node must do some action depending on the 2 higher order bits of the option type. When the higher order bits are 01, ...
2
votes
2answers
44 views

Do extension headers in IPv6 increase the header length

I was reading about IPv6. It says the header is of a fixed size i.e. 40 bytes, then how come is it able to accommodate extension headers. Doesn't this alter the size of headers. Please help, cant ...
2
votes
2answers
45 views

How to handle ICMP-in-IPv6 or ICMPv6-in-IPv4?

Since ICMP and ICMPv6 have different IP protocol numbers, it's technically possible for an IPv4 host to receive an ICMPv6 packet or for an IPv6 host to receive an ICMP packet. Is the host's behavior ...
2
votes
1answer
16 views

ipv6 dhcp pool option link-address

I'm learning to set up an ipv6 dhcp pool in Packet Tracer. And I'm stomped on what a link-address is as an option in a dhcp server ipv6. I've read this https://www.cisco.com/c/en/us/td/docs/ios-xml/...
5
votes
2answers
145 views

How to architect a globally distributed website, from an IP address perspective

I would like to have a website that is loaded fast from any point in the world. From my understanding, you need to take advantage of the data center "regions" at places like Google Cloud or AWS. That'...
2
votes
0answers
49 views

RPL: questions on routing mechanism

I'm studying RPL and two questions came to my mind: 1: Both in storing and non-storing modes, if a node wants to send a packet to another node via P2P communication paradigm, then how does the ...
7
votes
2answers
849 views

Why do IPv6 unique local addresses have to have a /48 prefix?

According to RFC 4193, unique local addresses will always have a prefix of FD00::/8.. but according to Wikipedia: The block fd00::/8 is defined for /48 prefixes, formed by setting the forty least-...
2
votes
1answer
39 views

What can an IP address be assigned to?

What can an IP address be assigned to? A network interface, which is what I thought originally. (I seem to hear a network interface can have multiple IP addresses assigned to it, and if it is true, ...
11
votes
3answers
1k views

Are the IPv6 address space and IPv4 address space completely disjoint?

Tanenbaum's Computer Networks says Finally, IPv4 addresses can be written as a pair of colons and an old dotted decimal number, for example: ::192.31.20.46 Does it mean the IPv4 address space ...
5
votes
2answers
762 views

Does IPv6 have similar concept of network mask?

Does IPv6 have similar concept of network mask? How does it represent a network? In the output of ifconfig, does prefixlen 128 represent a network mask? lo: flags=73<UP,LOOPBACK,RUNNING> mtu ...
4
votes
1answer
104 views

IPv6 default route not being installed from RA

Platform: Juniper SRX300 Version: JUNOS 15.1X49-D160.2 ISP: Midco I currently have an issue where the IPv6 default route is not being installed from the CMTS RA. Try as I might, I cannot get ...
3
votes
1answer
59 views

IPv6 Wireshark filter for partial IP address

I would like to create a display filter with the last 4 octets of an IPv6 address. Basically, I have the mac address with me and I want to filter for the IP address xxxx:xxxx:xxxx:xxxx:113:5005:80:...
1
vote
1answer
36 views

IPv4 only host on a dual stack environment

I am looking into migrating to IPv6 at my company. Our plan is to dual-stack everything for now, however, we have a couple of local servers that are IPv4 capable only. The rest of our network will be ...
2
votes
1answer
25 views

How to convert size represented in one prefix length to another?

Example, let's say if someone says, I have allocated one /64 address. How can I convert that to a size in /30? How many /30 equals to one /64?
1
vote
2answers
89 views

How are IPv6 addresses grouped? [closed]

I apologise off the bat if this question is too basic to belong in this group. Perhaps it can be moved elsewhere if that's the case, or I can be directed to another SE site. With IPv4 I have long ...
0
votes
2answers
47 views

Security implications of IPv6 tunneling over IPv4

I've read that IPv6 over IPv4 tunnels are a security risk because IPv6 traffic cannot be intercepted by Intrusion Detection Systems and Firewalls. This apparently deterred some networks to deploy IPv6....
1
vote
1answer
35 views

Where is the block which caused IPV4 client can not access IPV6 Server

I read many documents which are saying if you are in IPV4 network then you can not access IPV6 network, for example when I was at home I can not access some IPV6 website, such as:ipv6test.google.com. ...
0
votes
0answers
60 views

Mininet - Configure an IPv6 Router

There are a handful of examples for adding an IPv4 Router in a mininet topology. What there are almost no examples of, is how to add an IPv6 Router in a topology. I have read a few posts on the ...
4
votes
1answer
366 views

Will the packet be dropped when the number of hops equals to default TTL?

From my understanding, the default TTL represents the maximum number of hops allowed such that the packet may reach the host. NTP Documentation Archive: ttl - This option is used only with ...
2
votes
1answer
44 views

Can mobile devices take a global IPv6 address by means of only routing?

I'm probably asking this the wrong way, but here it is; I have a /48 block with static addresses for every device on the network. Everything is routed, no NAT, no tricks. My question is: on a mobile ...
2
votes
1answer
39 views

Why aren't we encrypting data on Network level instead of transport level when using e.g. HTTP [closed]

Why we are bothering to encrypt our data on a transport level, instead of just doing that on a network level with e.g. IPSec and get rid of the need to to that in upper layers. For example instead of ...
0
votes
1answer
52 views

IPv6 variables or other methods of shortening

From the dawn of when I heard about IPv6 many years ago, to my continued hesitance to make good use of it in today's world where it's eventually going to become necessary... my biggest issue I think ...
1
vote
1answer
63 views

Which part of an IPv6 address is assigned by the RIR?

Given my PC or any other, which part of the IPv6 address is allocated by the RIR and which part is allocated by the ISP? I know a prefix of /64 is commonly used, does that mean the bits before the /...
6
votes
4answers
757 views

OSI layer of Neighbor Discovery Protocol

NDP operates using ICMPv6 and, even though ICMPv6 messages are encapsulated in payload field of IPv6 datagram, ICMPv6 and ICMP are usually considered as network layer protocols. At least, on Wikipedia ...
2
votes
1answer
30 views

Global Unicast in IPv6 Neighbor Discovery

I have a very small pcap file in which Neighbor Discovery is performed for Global Unicast Addresses. That is, IPv6 addresses of both neighbors as I can see in Wireshark start from 2001:. Both IPv6 ...
1
vote
2answers
138 views

Link Local Address using in NDP (IPv6)

How is using of link local address in NDP. We can discover neighbor by using global address. So why we need link local address in NDP?
2
votes
1answer
49 views

IPV6 ping, the pinged address is different from the once caught by wireshark

I'm trying to ping an ECU, both PC and ECU have static IPV6 address the problem is that the target address (ECU) pinged is different from the one caught by Wireshark subnet : 64 ping command $ ...
2
votes
0answers
48 views

DHCP ivp6 vs DHCP ipv4 router config (cisco)

When setting up a router as dchp server in ipv4, we specify a pool under which we give the network and the default-gateway and that's it: However in ipv6 stateless dhcp , we create the pool then ...
7
votes
1answer
258 views

Is the first address of the subnet a valid configurable address in case of IPv4 and IPv6 point to point networks?

Am I correct, that first address of the subnet is a valid addresses to configure in hosts/routers in case of IPv4 and IPv6 point to point networks? For example, in case of 192.0.2.0/31 one of the ...
2
votes
2answers
403 views

IPv6 can't ping host when static route configured with exit interface

I have the following topology (using IPv6) interfaces: I have the following static routes configured on it: R1#sh ipv6 route static IPv6 Routing Table - default - 9 entries Codes: C - Connected, L -...
3
votes
3answers
63 views

Native IPv6 load balancing

We have two software gateways (on Linux) for IPv6 that take fullviews from ISPs and announce our AS. And several nodes connected to Internet via the gateways. Something like at picture: And we ...
1
vote
1answer
120 views

Why command “ipv6 dhcp relay” doesn't work at packet tracer?

I'm trying to enable dhcp for ipv6 with the "ipv6 dhcp relay dest" command but, I'm receiving an error and I'm trying both of these commands but none work. Router model: 2811 (config)# interface [...
3
votes
1answer
43 views

Quagga router advertisement messages are wrong after an address change

I have a problem with Quagga OSPFv3 implementation. I have a Mininet topology with a host connected to a router. I assigned an IPv6 address to the router interface. And I enabled IPv6 ...
4
votes
0answers
182 views

HSRP IPv6 configuration

Looking at the Cisco documentation for HSRP IPv6 configuration I noticed the use of 'standby 1 ipv6 autoconfig'. interface FastEthernet0/0 no ip address duplex auto speed auto ipv6 address 2020:...
5
votes
1answer
61 views

Disadvantages or risks of leaving the the family inet6 configuration under interface configuration in Junos applied

I have a corner-case where I need to leave the family inet6 configuration under IFL present while hosts in that network should not use IPv6. This means, that the logical interface of a router will ...
6
votes
1answer
61 views

How to set IPv6 RA values for RDNSS and DNSSL on HPE/Aruba 5400R

I am detail-planning the roll out of IPv6 in our company. Right now I am stuck with IPv6 RA on our HPE/Aruba Access Switches. I cannot find any documentation how to set the Recursive DNS Server (RDNSS)...
1
vote
1answer
77 views

IPv6 source address selection: can the source address have a smaller scope than the destination address?

In RFC 6724 section 5 on "Source Address Selection" rule 2 says to "Prefer appropriate scope": If Scope(SA) < Scope(SB): If Scope(SA) < Scope(D), then prefer SB and otherwise prefer SA. ...
0
votes
1answer
62 views

Why are there IP collisions in my network? [closed]

So I have a switch connected to ethernet cable which has a static IP address configured on it for IPv4 / v6. there are 3 IPv4 static addresses on its subnet. I have 2 Anritsu callboxes connected to ...
2
votes
1answer
189 views

Does IPv6 Prefix Delegation work with SLAAC, without the need of a DHCPv6 server/client?

All the (cisco) documentation I found about this topic always uses a DHCPv6 server or client to configure Prefix Delegation. But I never read that this is a requirement. Can Prefix Delegation be ...
1
vote
0answers
38 views

Using IPv6 6in4 tunnel with multiple VLANs, or LAN Interfaces?

I have a pfSense router, and I've setup a Hurricane 6in4 IPv6 tunnel by following this guide: http://thirdinternet.com/wp-content/uploads/2017/11/Configure-6in4-Tunnel-in-pfSense.pdf It all seems to ...
9
votes
1answer
826 views

What is the use-case of including the IPv4 address in IPv6 address?

It is possible to include the IPv4 address into IPv6 address. For example, 2001:db8::c0a8:6301 where last 32 bits are IPv4 address 192.168.99.1. There is even a special notation of IPv6 address where ...
1
vote
1answer
44 views

How can know the subnet mask in IPv6 network?

How the host can know the subnet mask in the IPv6 network, in case the network does not use the default subnet mask which is /64. for example the subnet mask of the network is /88, How can the IPv6 ...
5
votes
1answer
469 views

How does router advertisement in IPv6 avoid IP conflict?

If a router advertisement sends the range of subnet, and the client can choose an IP from it, how is there no conflict with another client that has chosen the same address?
0
votes
1answer
85 views

Can't connect between an IPV6 network and an added IPV4 router

I have a very simple topology, where 4 routers use IPV6 and RIP, there aren't problems and all devices have connectivity. The issue is if I add another router this time using IPV4 for clients. I ...
1
vote
2answers
96 views

Is it possible to see a Teredo IPv6 address in IPv6 neighbor cache?

Is it possible to see a Teredo address (from 2001::/32 block) in an IPv6 neighbor cache? For example, in the case of Junos, in the output of show ipv6 neighbors. As much as I tested, this is not ...
1
vote
1answer
36 views

Is it possible that IPv6 multicast address is shown in the “IPv6 Address” column of the “show ipv6 neighbors” command in Junos?

Is it possible that IPv6 multicast address(i.e address from ff00::/8 address block) is shown in the "IPv6 Address" column of the "show ipv6 neighbors" command in Junos?
58
votes
7answers
15k views

Why are IPv4 addresses running out?

I understand that we are running out (or ran out already?) of IPv4 addresses, but I don't really understand why that is. Right now, every home has its own IPv4 address (dynamically assigned, but still,...
1
vote
2answers
698 views

How to check if switch is ipv6 fully compatible

We will move to IPv6 in the next months and I have a lot of switches and routers and I want to discard IPv6 non-compatible or not fully compatible devices. What kind of standar I will need to check ...