In　communication　networks　that　span　large　geographical　regions,　transfer　of　bulk　data　is　often　costly　and　hard　to　manage.　One　prominent　reason　for　that　is　bandwidth　contention　among　long-lasting　flows,　and　between　long-lasting　and　short-lived　ones　on　inter-datacenter　links.　Delaying　the　transfer　of　bulk　data　to　off-peak　hours　by　temporarily　storing　transfer　at　edge　of　the　network　can　help　reduce　bandwidth　contention　during　peak　hours,　and　improve　overall　bandwidth　utilization　and　network　utility.　Although　extensive　research　has　been　conducted　on　its　use,　to　date　no　model　has　been　developed　to　quantify　the　performance　of　storage　assisted　bulk　transfers　across　multiple　congested　links.　This　research　gap　has　limited　our　understanding　of　the　operation　of　storage　assisted　transfer　under　different　network　conditions.　In　this　paper,　we　model　bulk　data　transfer　in　inter-datacenter　optical　networks　with　edge　storage,　and　derive　closed-form　equations　for　bulk　data　transfer　on　inter-DC　links　that　exhibit　diurnal　traffic　patterns　and　varying　peak　hours.　Our　study　reveals　that　when　the　data　transfer　requests　arrive　uniformly　in　a　day,　the　probability　of　a　successful　transfer　increases　linearly　with　the　time　data　is　allowed　to　wait　in　edge　storage.　Our　study　also　shows　that　this　probability　decreases　linearly　with　beta　+　D,　where　beta　and　D　are　the　durations　of　background　traffic　peak　and　size　of　data　transfers,　respectively,　when　the　network　is　moderately　loaded.　And,　the　benefit　of　storage　will　barely　increase　when　the　allowed　waiting　time　goes　beyond　beta　+　D.