update

1 files changed, 10 insertions, 4 deletions

diff --git a/assignments/1/README.md b/assignments/1/README.md
index 34bb1c7..0ee9636 100644
--- a/assignments/1/README.md
+++ b/assignments/1/README.md
@@ -266,10 +266,13 @@ a) Number of packets
 
 b) Links (via traceroute)
 - Answer: In all three traces to www.athabascau.ca, the last responding hop was 7 (Telus backbone). Later hops filtered probes, so the total hop count to the destination could not be observed with ICMP/UDP traceroute.
-- Responding hops seen (from Run 1):
-  1) 192.168.0.1 (home router)
-  2) 10.139.230.1 (ISP gateway)
-  7) 154.11.15.105/154.11.15.107 (Telus backbone)
+- Identified hops from Run 1 (morning):
+  - Hop 1: _gateway (192.168.0.1) - home router
+  - Hop 2: 10.139.230.1 - ISP gateway (private address inside Telus network)
+  - Hops 3-6: no reply (likely ICMP/UDP filtered)
+  - Hop 7: QUBCPQBIDR03.bb.telus.com (154.11.15.105) and 154.11.15.107 - Telus backbone
+  - Hops 8-30: no reply
+  - Destination: www.athabascau.ca (3.175.64.80) - no reply
 
 c) Speed for each identified link
 - Answer (best estimate):
@@ -286,6 +289,9 @@ e) Time when the last packet arrives at the server
 - Add ~10-20 ms for propagation/processing (consistent with ~18.8 ms RTT to the last responding hop): 0.188 s + 0.010-0.020 s ~ 0.198-0.208 s
 - Answer: about t0 + 0.20-0.21 s
 
+Method note on traceroute filtering
+- Many networks de-prioritize or block ICMP/UDP TTL-expired replies. This can hide intermediate and destination hops even when the path is fine. Using TCP to port 443 often elicits more replies, but the assignment requires traceroute; therefore I report the last responding hop and include the full outputs for verification.
+
 ## 2.2 Propagation Delay and Bandwidth-Delay Product (20%)
 
 > (20%) Consider that you are submitting another assignment from your home computer to the university server, and you have worked out a list of network links between your computer and the university server.