on the implementation of the combined PGW and NAT64, the native IPv6 traffic should bypass the translation function entirely. Scalability is one of the main con- cerns of the combined NAT64 and PGW. The PGW already aggregates a lot of traffic and especially sessions. The scaling up traffic-wise typically means redundant nodes. Scal- ing up the number of sessions usually means (naively) more memory for session state information and either bigger IPv4 pools on the egress side of the NAT64 or smaller IPv6 Transition Mechanisms for 3GPP Networks Source Destination Protocol 46 0.003187 2001:1bc8:101:f192:ba27:ebff:fecc:a78e 2001:1bc8:101:f190:200:5e00:3213:628f ICMPv6 Echo (ping) request id-0x0a3f, seq-1 47 0.000815 192.168.89.190 50.19.98.143 Echo (ping) request id=0x0a3f. seq=1/25 48 0.143790 50.19.98.143 192.168.89.190 Echo (ping) reply id=0x0a3f. seq=1/25 49 O. 000413 2001:Ibc8:101:f190:200:5e00:3213:628f 2001:1bc8:101:f192:ba27:ebff:fecc:a78e ICMPv6 Echo (ping) reply id=0x0a3f. seq=1 (ping) 190 o 000949 192.168.89.190 92.122.91.80 Echo (ping) request id=0x0a42. seq=1/25 191 0.049019 92.122.91.80 192.168.89.190 Echo (ping) reply id=0x0a42, seq=1/256 192 0.000417 2001:1bcB:101:f190:200:5e00:5c7a:5b50 2001:1bc8:101:f192:ba27:ebff:fecc:a78e ICMPv6 Echo (ping) reply id=0x0a42 seq=1 267 o. 006781 2001:1bc8:101:f192:ba27:ebff:fecc:a78e 2001:1bc8:101:f190:200:5e00:5b79:4527 ICMPY6 Echo (ping) request id=0x0a49, seq=1 268 0.001036 192.168.89.190 91.121.69.39 Echo (ping) request id=0x0a49 seq=1/256 269 0.056526 91.121.69.39 192.168.89.190 Echo (ping) reply id=0x0a49, seq=1/256 270 o. 000410 2001:1bcB:101:f190:200:5e00:5b79:4527 2001:1bc8:101:f192:ba27:ebff:fecc:a7Be ICMPy6 Echo (ping) reply id=0x0a49 seq=1 Frame 189: 118 bytes on wire (944 bits). 118 bytes captured (944 bits) Ethernet II. Src: Routerbo_f7:ea:46 (00:0c:42:f7:ea:46) Dst: Raspberr 1a:83:c (b8:27:eb:1a:83:d5/ Internet Protocol Version 6. Src: 2001:1bc8:101:f192:ba27:ebff:fecc:a78e (2001:1bc8:101:f192:ba27:ebff: 2001:1bcB:101:f190:200:5 Internet Control Message