Hi Osmocom team. We are sorry to disturb you. We have a question about establishing a stable internet connection (IuPS_PS) between MS and our developed network core system using our home nodeB (HNB). We set *Primary DNS Address: 172.60.3.154 *(core IP) and *Secondary DNS Address: 8.8.8.8* in *Activate PDP Context Accept.* At this step, we can see the MS packets in the interface between HNB and core using wireshark. The protocol is *GTP <DNS>* and the stacked layers are *DNS / UDP / IP / GTP / UDP / IP* which I attached a screenshot of the wireshark log. As you can see in the attached image, our query in the MS is *server.hnb* *(http://server.hnb http://server.hnb)*. In order to show our default page to the user query, we set up a DNS server and HTTP server (Apache) in 172.60.3.154 and *BIND9* is configured as the primary server for the domain *server.hnb*. The command *dig @localhost server.hnb* outputs the following:

; <<>> DiG 9.16.1-Ubuntu <<>> @localhost server.hnb ; (1 server found) ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 49532 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4096 ; COOKIE: 15821f64047895870100000060070fb921a17af91fd22f9f (good) ;; QUESTION SECTION: ;server.hnb. IN A

;; ANSWER SECTION: server.hnb. 604800 IN A 172.60.3.154

;; Query time: 0 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: Jan 19 20:28:33 +0330 2021 ;; MSG SIZE rcvd: 83

and also when we query *http://server.hnb http://server.hnb *in the browser of the core system (172.60.3.154), we see the * Apache2 Ubuntu Default Page* but this default page is not shown in the MS. Furthermore, we think that a GTP tunnel may be required and we set up a GTP tunnel using *libgtpnl* and the two following commands:

gtp-link add gtp1 gtp-tunnel add gtp1 v1 1 100 10.250.0.114 172.60.3.154

where 1 is the gTP-TEI obtained in *RAB-Assignment Response *and 100 is the similar field in *RAB-Assignment Request. *Also, 10.250.0.114 is the MS IP and 172.60.3.154 is the core IP. But there is no captured package in this tunnel (using wireshark).

Could you please help us to solve this problem which is mentioned in the following questions? Is the above procedure performed in the correct way? We want to show our default page in MS when the user query is* http://server.hnb http://server.hnb*, but we think that a GTP manager is required to split the (( DNS / UDP / IP )) layers from (( DNS / UDP / IP / GTP / UDP / IP )) to send to DNS server. How can it be solved, if this assumption is correct?

Thank you again for spending time with us. Best regards, Morteza Ali Ahmadi