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Questions tagged [ipv6]

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

-1
votes
1answer
27 views

convert char array containing ipv6 address to dotted ipv6 format using network APIs in linux [on hold]

i want to convert an array type char contains raw IPv6 address to IPv6 dotted format using network APIs in Linux environment. eg: i/p = fe80000000000000020d41fffe121400 o/p = fe80:0000:0000:0000:020d:...
4
votes
1answer
312 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
38 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
37 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
0answers
149 views

how to configure ipsec with dynamic ipv6-pd on one side

my current network setup (simplified) looks like this The Current configuration (also simplified) permits traffic to flow between dc_dev and bo_dev and dc_man and bo_man freely and some special ...
0
votes
1answer
44 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
44 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
703 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
23 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
71 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
45 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
29 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
241 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
145 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
55 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
65 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
37 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
76 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
55 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 ...
3
votes
0answers
35 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
67 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
59 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
119 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
29 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
739 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
39 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
450 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
67 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
92 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
31 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?
56
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
284 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 ...
0
votes
1answer
49 views

Trade Floor Network Design Feedback [closed]

I have an assignment that I am working on. Now I admit, I am far from knowledgeable and I have nowhere to turn to for help at the moment. I am not asking for someone to complete the assignment for me, ...
1
vote
0answers
117 views

How is the source link-layer address in IPv6 router solicitation(RS) messages used?

When I analyze the router solicitation(RS) messages, then they contain the MAC address of the sending host. How does the router use this MAC address seen in ICMPv6 message? Does it simply use it as a ...
1
vote
2answers
135 views

How does WAN work?

I understand the basics. WAN is a network that connects multiple LANs together. Usually the router is the connection between the LAN and WAN. But I have some questions books and the internet could not ...
2
votes
2answers
195 views

If the IPv6 address will be strictly based on EUI-64 logic then is there any real need of Neighbour Discovery Protocol?

I am building my fundamentals on IPv6 and have realised the multicast group is nothing but FF02::1:FFXX:XXXX. Here xxx is nothing but 24-bits of Mac-address (48 bits) with simple 7th bit magic. ...
1
vote
1answer
398 views

What are the key advantages and disadvantages of NDP compared to ARP?

So why they didn't use ARP in IPv6? is there any real benefit of doing this? what are the key advantages and disadvantages of using NDP instead of ARP? (In overall network performance, Security and ...
0
votes
1answer
47 views

Implications of ipv6 on LAN security [duplicate]

I'm not sure whether this is really the correct place to post this question, because it's not really about a "professional" setting. However, I have the standard setup with computers behind a netgear ...
4
votes
1answer
222 views

IPv6 - ULAs - Am I understanding use correctly?

Tinkering more with IPv6 and trying to unlearn the IPv4 stuff. Assume my router is correctly respecting the reserved addresses. LLIPs aren't going to pass through to the router's outside interface ...
-1
votes
1answer
86 views

Is NATing possible in case of IPV6 addressing mode anyway?

Setup: A(2001::1:123) <------> B(2001::1:124) <------> C(2001::1:125) where A,B and C are the systems.And apply rule of NAT(SNAT/DNAT) on system B for forwarding a packets from C to B,B to C,A ...
2
votes
2answers
123 views

How does/did an ISP serve so many people over IPv4

Whilst reading Tanenbaum - Computer Networks they talk about IP scarcity at the level of ISPs: IP addresses are scarce. An ISP might have a /16 address, giving it 65,534 usable host numbers. If it ...
6
votes
1answer
574 views

Why is an IPv6 Link-Local Address a /10?

I'm currently studying for my CompTIA Network+ Exam and am a bit confused as to why the IPv6 link-local address is a /10 and not a /12 or /16. Since each character in an IPv6 address is 4-bits and ...
1
vote
1answer
45 views

ISATAP configuration not working when adding hosts

I am trying to make an ISATAP configuration where two ipv6 hosts connected to dual stacked routers can communicate to each other. I have the following configuration: I have configured RIP across ...
5
votes
0answers
348 views

How to break apart an IPv6 /56 6rd delegated prefix from ISP into multiple /64 VLANs for use with SLAAC EUI-64? [Cisco]

I have CenturyLink Internet service, and they have a 6RD IPv6 deployment where they hand out an IPv6 delegated prefix /56 block to me and allow me to use it as I wish. My Cisco ISR router receives the ...
0
votes
2answers
42 views

When neigbour solicitation and router solicitation are used to get the IPv6 address, then what is the role of 0:0:0:0:0:0:0:0/128?

I am learning computer networks, but getting confused each time I proceed my analysis. Kindly help. Thanks in advance!
-1
votes
1answer
58 views

Sending image files using GNS3

I had built a network using GNS3, this network contains a lot of routers, the problem is: I want to send an image file between these routers using GNS3 is there any way to do that?
3
votes
1answer
460 views

Network flooded with ICMPv6 Multicast Listener Report Packets

I recently noticed that 3 out of 4 Unifi APs kept reaching 100% CPU usage. When I jumped onto the networks and took a Wireshark capture I noticed 1000s of these packets being sent in just a matter of ...
5
votes
2answers
177 views

Is Path MTU Discovery(PMTUD) really efficient?

As i know, PMTUD uses ICMPv6 to find minimum MTU value in the network path. I understood why IPv6 doesn't allow fragmentation (by reading this article), but PMTUD doesn't look like good manner. here ...
6
votes
2answers
3k views

Is it true that the fd00::/8 address range (ULA) in ipv6 is for machines that you NEVER want to speak with anything on the Internet?

Is it true that the fd00::/8 address space (User Local Addresses) in ipv6 is for machines that you NEVER want to speak with anything on the Internet? I was just reading that here and rather surprised ...
1
vote
2answers
591 views

no default-router option in dhcpv6?

I'm learning how to program a Cisco router with dhcpv6 and i saw that they never configure the default gateway address in the dhcpv6 configuration . Then how can the pc know what it's gateway address ...